PC Architecture, Peripherals and Mobile devices
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Trademarks: All brand names and product names included in this tutorial are trademarks, registered trademarks, or trade names of their respective holders.
Motherboards
Memory
CD-ROM / DVD’s
Hard Disk Drive
Inkjet Printer
Monitor
Modem / WiFi / Router
Keyboard
Mouse
Scanners
Digital Camera
Laptop / USB Flash Drive
iPad / iPhone
Kindle Fire / The Nook
iPod / Bluetooth
Acknowledgements
More EBooks by this Author
In The Beginning...
The history of computers starts out over 2000 years ago, at the birth of the abacus, a wooden rack holding two horizontal wires with beads strung on them. When
these beads are moved around, according to programming rules memorized by the user, all regular arithmetic problems can be done. Another important invention
around the same time was the Astrolabe, used for navigation.
Blaise Pascal is usually credited for building the first digital computer in 1642. It added numbers entered with dials and was made to help his father, a tax collector.
In 1671 Gottfried Wilhelm von Liebniz invented a computer that was built in 1694. It could add, and, after changing some things around, multiply. Liebniz invented
a special stepped gear mechanism for introducing the addend digits, and this is still being used.
The prototypes made by Pascal and Leibniz were not used in many places, and considered weird until a little more than a century later, when Thomas of Colmar
(A.K.A. Charles Xavier Thomas) created the first successful mechanical calculator that could add, subtract, multiply, and divide.
2
Charles Babbage
While Thomas of Colmar was developing the desktop calculator, a series of very interesting developments in computers was started in Cambridge,
England, by one Charles Babbage (after which the computer store "Babbages" is named), a mathematics professor. In 1812, Babbage realized that
many long calculations, especially those needed to make mathematical tables, were really a series of predictable actions that were constantly
repeated. From this he suspected that it should be possible to do these automatically.
He began to design an automatic mechanical calculating machine, which he called a difference engine. By 1822, he had a working model to
demonstrate with. With financial help from the British government, Babbage started fabrication of a difference engine in 1823. It was intended to be steam
powered and fully automatic, including the printing of the resulting tables, and commanded by a fixed instruction program.
The difference engine, although having limited adaptability and applicability, was really a great advance. Babbage continued to work on it for the next 10 years, but
in 1833 he lost interest because he thought he had a better idea -- the construction of what would now be called a general purpose, fully program-controlled,
automatic mechanical digital computer. Babbage called this idea an Analytical Engine. The ideas of this design showed a lot of foresight, although this couldn’t be
appreciated until a full century later.
Babbage's computers were never finished. Various reasons are used for his failure. Most used is the lack of precision machining techniques at the time. Another
speculation is that Babbage was working on a solution of a problem that few people in 1840 really needed to solve. After Babbage, there was a temporary loss of
interest in automatic digital computers.
Other inventions
Babbage is also credited with the cowcatcher, dynamometer, standard railroad gauge, uniform postal rates, occulting lights for lighthouses, Greenwich time
signals, and the heliograph ophthalmoscope. He also had an interest in cyphers and lock-picking, but abhorred street musicians.
Babbage observed
Near the northern pole of the moon there is a crater named for Charles Babbage. When he died in 1871, however, few people knew who he was. Only one carriage
(the Duchess of Somerset's) followed in the burial procession that took his remains to Kensal Green Cemetery. The Royal Society printed no obituary, and the
Times ridiculed him. The parts of the Difference Engine that had seemed possible of completion in 1830 gathered dust in the Museum of King's College.
In 1878 The Cayley committee told the government not to bother constructing Babbage's Analytical Engine. By the 1880's Babbage was known primarily for his
reform of mathematics at Cambridge. In 1899 the magazine Temple Bar reported that "the present generation appears to have forgotten Babbage and his
calculating machine". In 1908, after being preserved for 37 years in alcohol, Babbage's brain was dissected by Sir Victor Horsley of the Royal Society. Horsley had
to remind the society that Babbage had been a "very profound thinker". He is thought about, if at all, as a funny sort of distracted character with a dirty collar, but
he was in fact, an amazing intelligence.
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Motherboards
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The main circuit of a microcomputer. The motherboard contains the connectors for attaching additional boards. Typically, the motherboard contains the CPU
(Central Processing Unit), BIOS (Basic Input Output System), Memory (RAM), mass storage (internal hard disk drive(s), expansion slots for adding new hardware
cards) e.g. modem card, graphics card video card etc and all the controllers required to control standard peripheral devices e.g. the monitor (display screen),
keyboard and disk drive(s). On most PCs memory chips are slotted directly onto the motherboard. You may also be able to upgrade to a faster PC by replacing the
CPU chip. To add additional core features, you may need to replace the motherboard entirely.
The Microprocessor chip
(CPU)
If you are using your computer to read this page, your microprocessor is making this possible. The microprocessor is the heart of any normal computer, whether it
is a desktop machine, a server (a single computer that communicates with multiple other computers) or a laptop. The microprocessor you are using might be a
Pentium, a Celeron, a AMD, a K6, a PowerPC, a Sparc or any of the many other brands and types of microprocessors, but they all do approximately the same thing
in approximately the same way, whether its spell checking a document, displaying a complex graphic image or playing a game.
CPU chip
Motherboard
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Memory (RAM)
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Main memory
A PC's principal level of system memory is referred to as main memory, or Random Access Memory
(RAM). It is an impermanent source of data, but is the main memory area accessed by the hard disk. It
acts, so to speak, as a staging post between the hard disk and the processor. The more data it is possible
to have available in the RAM the faster the PC will run. (4 GB RAM will usually ensure that your
applications run at optimum speed)
Main memory is attached to the processor via its address and data buses. Each bus consists of a number
of electrical circuits or bits. The width of the address bus dictates how many different memory locations
can be accessed, and the width of the data bus how much information is stored at each location. Every
time a bit is added to the width of the address bus, the address range doubles.
RAM Basics
Memory is made up of bits (0’s and 1’s) arranged in a two-dimensional grid.
Similar to a microprocessor, a memory chip is an integrated circuit (IC) made of millions of transistors and capacitors. In the most common form of computer
memory, dynamic random access memory (DRAM), a transistor and a capacitor are paired to create a memory cell, which represents a single bit of data (either 0
or 1). The capacitor holds the bit of information. The transistor acts as a switch that lets the control circuitry on the memory chip read the capacitor or change its
state. A capacitor is like a small bucket that is able to store electrons. To store a 1 in the memory cell, the bucket is filled with electrons. To store a 0, it is emptied.
The problem with the capacitor's bucket is that it has a leak. In a matter of a few milliseconds a full bucket becomes empty. Therefore, for dynamic memory to
work, either the CPU or the memory controller has to come along and recharge all of the capacitors holding a 1 before they discharge. To do this, the memory
controller reads the memory and then writes it right back. This refresh operation happens automatically thousands of times per second.
Memory cells are etched onto a silicon wafer in an array of columns and rows. The intersection of a column and row constitutes the address of the memory cell.
Disk Cache
In computer science, a portion of a computer’s random access memory (RAM) that is set aside for temporary storage of information. Disk cache is used to hold
information that has recently been requested from disk or has been written to disk. For example, a program might need to read the same portions of a data file
repeatedly from disk. If the required information remains in a disk cache, access time is considerably reduced, as the program does not have to wait for the disk
drive mechanism to fetch the information from the disk each time it is required.
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The CD-ROM
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When Sony and Philips invented the Compact Disc (CD) in the early 1980s, even they couldn't ever have imagined what a versatile carrier of information it would
become. Launched in 1982, the audio CD's durability, random access features and audio quality made it incredibly successful, capturing the majority of the market
within a few years. CD-ROM followed in 1984, but it took a few years longer to gain the widespread acceptance enjoyed by the audio CD. This consumer reluctance
was mainly due to a lack of compelling content during the first few years that the technology was available. However, there are now countless games, software
applications, encyclopaedias, presentations and other multimedia programs available on CD-ROM and what was originally designed to carry 74 minutes of highquality digital audio can now hold up to 650MB of computer data, 100 publishable photographic scans, or even 74 minutes of VHS -quality full-motion video and
audio. Many discs offer a combination of all three, along with other information besides. Today's mass produced CD-ROM drives are faster and
cheaper than they've ever been. Consequently, not only is a vast range of software now routinely delivered on CD-ROM, but many programs
e.g. databases, multimedia titles, games and movies, are also run directly from CD-ROM, often over a network.
DVDs Technology
At first glance, a DVD disc can easily be mistaken for a CD: both are plastic discs 120mm in diameter and 1.2mm thick and both rely on lasers to
read data stored in pits in a spiral track. And whilst it can be said that the similarities end there, it's also true that DVD's seven-fold increase in
data capacity over the CD has been largely achieved by tightening up the tolerances throughout the predecessor system.
Firstly, the tracks are placed closer together, thereby allowing more tracks per disc. The DVD track pitch (the distance between each) is reduced to 0.74 micron,
less than half of CD's 1.6 micron. The pits, in which the data is stored, are also a lot smaller, thus allowing more pits per track. The minimum pit length of a single
layer DVD is 0.4 micron as compared to 0.834 micron for a CD. With the number of pits having a direct bearing on capacity levels, DVD's reduced track pitch and pit
size alone give DVD-ROM discs up to ten times the storage capacity of CDs.
The packing of as many pits as possible onto a disc is, however, the simple part and DVD's real technological breakthrough was with its laser. Smaller pits mean
that the laser has to produce a smaller spot, and DVD achieves this by reducing the laser's wavelength from the 780nm (nanometers) infrared light of a standard
CD, to 635nm or 650nm red light.
Secondly, the DVD specification allows information to be scanned from more than one layer of a DVD simply by changing the focus of the read laser. Instead of
using an opaque reflective layer, it's possible to use a translucent layer with an opaque reflective layer behind carrying more data. This doesn't quite double the
capacity because the second layer can't be quite as dense as the single layer, but it does enable a single disc to deliver 8.5GB of data without having to be removed
from the drive and turned over. An interesting feature of DVD is that the discs' second data layer can be read from the inside of the disc out, as well as from the
outside in. In standard-density CDs, the information is always stored first near the hub of the disc.
Thirdly, DVD allows for double-sided discs. To facilitate the focusing of the laser on the smaller pits, manufacturers used a thinner plastic substrate than that used
by a CD-ROM, thereby reducing the depth of the layer of plastic the laser has to travel through to reach the pits.
Finally, DVD has made the structure of the data put on the disc more efficient. When CD was developed in the late 1970s, it was necessary to build in some heavyduty and relatively crude error correction systems to guarantee the discs would play. When bits are being used for error detection they are not being used to carry
useful data, so DVD's more efficient and effective error correction code leaves more room for real data.
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The Hard Disk Drive (HDD)
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Operation
The disc platters are mounted on a single spindle that spins at a typical 10,000rpm
Data is recorded onto the magnetic surface of a platter in exactly the same way as it is
on floppies or digital tapes. Essentially, the surface is treated as an array of dot positions,
with each domain of magnetic polarisation being set to a binary 1 or 0. The position of
each array element is not identifiable in an absolute sense, and so a scheme of guidance
marks helps the read/write head find positions on the disk. The need for these guidance
markings explains why disks must be formatted before they can be used.
When it comes to accessing data already stored, the disk spins round very fast so that
any part of its circumference can be quickly identified. The drive translates a read
request from the computer into reality. There was a time when the cylinder/head/sector
location that the computer worked out really was the data’s location, but today’s drives
are more complicated than the BIOS can handle, and they translate BIOS requests by
using their own mapping.
When the computer wants to read data, the operating system works out where the data is on the disk. To do this it first reads the FAT (File Allocation Table) at the
beginning of the partition. This tells the operating system in which sector on which track to find the data. With this information, the head can then read the
requested data. The disk controller controls the drive’s servo-motors and translates the fluctuating voltages from the head into digital data for the CPU.
More often than not, the next set of data to be read is sequentially located on the disk. For this reason, hard drives contain between 256KB and 8MB of cache
buffer in which to store all the information in a sector or cylinder in case it’s needed. This is very effective in speeding up both throughput and access times. A hard
drive also requires servo information, which provides a continuous update on the location of the heads. This can be stored on a separate platter, or it can be
intermingled with the actual data on all the platters. A separate servo platter is more expensive, but it speeds up access times, since the data heads won’t need to
waste any time sending servo information.
However, the servo and data platters can get out of alignment due to changes in temperature. To prevent this, the drive constantly rechecks itself in a process
called thermal recalibration. During multimedia playback this can cause sudden pauses in data transfer, resulting in stuttered audio and dropped video frames.
Where the servo information is stored on the data platters, thermal recalibration isn’t required. For this reason the majority of drives embed the servo information
with the data. (Ref. PC Tech Guide)
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The Inkjet Printer
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Inkjet printers are the most common type of consumer printers. The inkjet technology works by spraying very
fine drops of ink on a sheet of paper. These droplets are "ionized" which allows them to be directed by
magnetic plates in the ink's path. As the paper is fed through the printer, the print head moves back and
forth, spraying thousands of these small droplets on the page.
While inkjet printers used to lack the quality and speed of laser printers, they have become almost as fast as
laser printers and some can even produce higher-quality images. Even low-budget inkjet printers can now
print high-resolution photos. The amazing thing is, as the quality of inkjet printers has improved, the prices
have continued to drop. However, for most people, refilling the inkjet cartridges a few times will often cost
more than the printer. (Ref. Tech terms)
There are several types of inkjet technology but the most common is "drop on demand" (DOD). This works by
squirting small droplets of ink onto paper, through tiny nozzles: like turning a hosepipe on and off 5,000 times
a second. The amount of ink propelled onto the page is determined by the driver software that dictates which
nozzles shoot droplets, and when.
DPI (Dots per inch)
Up to a point, printers with higher DPI produce clearer and more detailed output. A printer does not necessarily have a single DPI measurement; it is dependent on
print mode, which is usually influenced by driver settings. The range of DPI supported by a printer is most dependent on the print head technology it uses. A dot
matrix printer, for example, applies ink via tiny rods striking an ink ribbon, and has a relatively low resolution, typically in the range of 60 to 90 DPI (420 to 280 µm).
An inkjet printer sprays ink through tiny nozzles, and is typically capable of 300–720 DPI. A laser printer applies toner through a controlled electrostatic charge,
and may be in the range of 600 to 2,400 DPI. (Ref. Wikipedia)
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A modern LCD Monitor
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The LCD (liquid crystal display) monitor is a common item on the desktop nowadays. They are used in Laptop computers,
digital clocks and watches, microwave ovens, CD players and hundreds of other electronic devices. LCD’s are common
because they offer some real advantages over other display technologies. They are thinner and lighter and draw much less
power than the outdated cathode ray tubes (CRTs), for example.
But just what are these things called liquid crystals? The name "liquid crystal" sounds like a contradiction. We think of a
crystal as a solid material like quartz, usually as hard as rock, and a liquid is obviously different. How could any material
combine the two?
We learned in school that there are three common states of matter: solid, liquid or gaseous. Solids act the way they do
because their molecules always maintain their orientation and stay in the same position with respect to one another. The
molecules in liquids are just the opposite: They can change their orientation and move anywhere in the liquid. But there are some substances that can exist in an
odd state that is sort of like a liquid and sort of like a solid. When they are in this state, their molecules tend to maintain their orientation, like the molecules in a
solid, but also move around to different positions, like the molecules in a liquid. This means that liquid crystals are neither a solid nor a liquid. That's how they
ended up with their seemingly contradictory name.
So, do liquid crystals act like solids or liquids or something else? It turns out that liquid crystals are closer to a liquid state than a solid. It takes a fair amount of heat
to change a suitable substance from a solid into a liquid crystal, and it only takes a little more heat to turn that same liquid crystal into a real liquid. This explains
why liquid crystals are very sensitive to temperature and why they are used to make thermometers and mood rings. It also explains why a laptop computer display
may act strangely in cold weather or during a hot day at the beach.
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WiFi
The Modem
A modem (modulator-demodulator) is a device that modulates an
analogue carrier signal to encode digital information and demodulates the
signal to decode the transmitted information. The goal is to produce
a signal that can be transmitted easily and decoded to reproduce the
original digital data.
Internet
WiFi
WiFi is a local area wireless technology that allows an electronic device to
exchange data or connect to the internet using 2.4 GHz UHF and
5 GHz SHF radio waves.
Many devices can use Wi-Fi, e.g. personal computers, video-game consoles,
smart-phones, some digital cameras, tablet computers and digital audio
players. These can connect to a network resource such as the Internet via
a wireless network access point. Such an access point (or hotspot) has a range of about 20 meters (66 feet) indoors and a greater range outdoors. Hotspot
coverage can comprise an area as small as a single room with walls that block radio waves, or as large as many square kilometres achieved by using multiple
overlapping access points. (Ref. Wikipedia)
A typical Router Modem
The Router Modem combination
While the router and modem are usually separate entities, in some cases, the modem and
router may be combined into a single device. This type of hybrid device is sometimes offered
by ISPs (Internet Service Providers) to simplify the setup process.
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The Keyboard
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A computer keyboard is a peripheral partially modelled after the typewriter keyboard. Keyboards are designed for the input of text and characters and also to
control the operation of a computer.
There exist a large number of different arrangements of symbols on keys. These different keyboard layouts arise
mainly because different people need easy access to different symbols; typically, this is because they are writing in
different languages, but specialized keyboard layouts for mathematics, accounting, and computer programming also
exist.
Most of the more common keyboard layouts (QWERTY-based and similar) were designed in the era of the
mechanical typewriters, so their ergonomics had to be slightly compromised in order to tackle some of the technical
limitations of the typewriters. With the advent of modern electronics, this is no longer necessary. The letters were
attached to levers that needed to move freely; jamming would result if commonly-used letters were placed too
close to one another. QWERTY layouts and their brethren had been a de facto standard for decades prior to the
introduction of the very first computer keyboard, and were primarily adopted for electronic keyboards for this
reason. Alternative layouts do exist, such as the Dvorak Simplified Keyboard; however, these layouts are not in
widespread use.
The number of keys on a keyboard varies from the original standard
of 101 keys to the 104-key windows keyboards and all the way up to
130 keys or more, with many of the additional keys being symbolless programmable keys e.g. starting a web browser or e-mailing a
client. There also were "Internet keyboards," sold in America in the
late 1990s, that replaced the function keys with pre-programmed
internet shortcuts. A computer keyboard distinguishes each physical
key from every other and reports all key presses to the controlling
software. Keyboards are also used for computer gaming and some
are fitted with special gaming features, which can expedite
frequently used keystroke combinations. A keyboard is also used to
give commands to the operating system of a computer, such
as Windows' Control-Alt-Delete combination, which brings up a task
window or shuts down the machine.
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The Mouse
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The Early Mouse
In the early 1980s the first PCs were equipped with the traditional user input device - a keyboard. By the
end of the decade however, a mouse device had become an essential for PCs running the GUI (Graphics
User Interface) based Windows operating system.
Gone are the old roller ball mice which were apt to gather fluff and other detritus on the ball and
required regular cleaning.
------------------------------------------------------------------------------------------------------------The Optical mouse
The optical computer mouse uses a light-emitting diode and photodiodes to detect movement relative
to a surface. The earliest optical mice detected movement on pre-printed mousepad surfaces, whereas
the modern optical mouse works on most opaque surfaces, it is usually unable to detect movement on
reflective surfaces like glass, although some advanced models can function even on clear glass.
Battery powered, wireless optical mice flash the LED intermittently to save power, and only glow
steadily when movement is detected. (Ref. Wikipedia)
------------------------------------------------------------------------------------------------------------The Laser Mouse
The laser mouse uses an infrared laser diode instead of a LED to illuminate the surface beneath their
sensor.
The laser illumination enables superior surface tracking compared to LED-illuminated optical mice, but
can pose a health risk if pointed directly at one's eye. (Ref. Wikipedia)
-------------------------------------------------------------------------------------------------------------
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Scanners
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Digital imaging has come of age. Equipment that was once reserved for the wealthiest bureaux is now
commonplace on the desktop. The powerful PCs required to manipulate digital images are now considered entry
level, so it comes as no surprise to learn that scanners, the devices used to get images into a PC, are one of the
fastest growing markets today.
At its most basic level, a scanner is just another input device, much like a keyboard or mouse, except that it takes
its input in graphical form. These images could be photographs for retouching, correction or used in DTP (Desktop
Publishing). They could be hand-drawn logos required for document letterheads. They could even be pages of text
which suitable software could read and save as an editable text file.
The list of scanner applications is almost endless, and has resulted in products evolving to meet specialist
requirements:

high-end drum scanners, capable of scanning both reflective art and transparencies, from 35mm slides to 16-foot x 20in material at high (10,000dpi+)
resolutions

compact document scanners, designed exclusively for OCR (Optical Character Recognition) document management

dedicated photo scanners, which work by moving a photo over a stationary light source

slide/transparency scanners, which work by passing light through an image rather than reflecting light off it

hand-held scanners, for the budget end of the market or for those with little desk space.
Flatbed scanners however, are the most versatile and popular format. These are capable of capturing colour pictures, documents, pages from books and
magazines, and, with the appropriate film holders, can scan colour slides and negatives as well.
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Digital cameras
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It's easy to understand the booming business that digital camera manufacturers are doing these days. The host of
easy-to-use personal and business publishing applications, the dramatic expansion of the Web and its insatiable
appetite for visual images, and the proliferation of inexpensive printers capable of photo-realistic output make a
digital camera an enticing add-on. Those factors, combined with improving image quality and falling prices, put the
digital camera on the cusp of becoming a standard peripheral for a home or business PC.
In principal, a digital camera is similar to a traditional film-based camera. There's a viewfinder to aim it, a lens to
focus the image onto a light-sensitive device, some means by which several images can be stored and removed for
later use, and the whole lot is fitted into a box. In a conventional camera, light-sensitive film captures images and is
used to store them after chemical development. Digital photography uses a combination of advanced image sensor
technology and memory storage, which allows images to be captured in a digital format that is available instantly with no need for a "development" process.
Although the principle may be the same as a film camera, the inner workings of a digital camera are quite different, the imaging being performed either by a CCD
(charge coupled device) or CMOS (complementary metal-oxide semiconductor) sensors. Each sensor element converts light into a voltage proportional to the
brightness which is passed into an ADC (analogue-to-digital converter) which translates the fluctuations of the CCD into discrete binary code. The digital output of
the ADC is sent to a DSP (digital signal processor) which adjusts contrast and detail, and compresses the image before sending it to the storage medium.
The brighter the light the higher the voltage and the brighter the resulting computer pixel. The more elements, the higher the resolution, and the greater the
detail that can be captured.
This entire process is very environment-friendly. The CCD or CMOS sensors are fixed in place and it can go on taking photos for the lifetime of the camera. There's
no need to wind film between two spools either, which helps minimise the number of moving parts.
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Laptop Computer (Notebook)
A small portable computer ranging from 5-20 pounds which may be used conveniently on business trips, in classrooms, and in other situations where traditional
personal computers may be less efficient.
Laptops usually run on a single battery or from an external AC/DC adapter which can charge the battery while
also supplying power to the computer itself.
As personal computers, laptops are capable of the same tasks as a desktop PC. They contain components that
are similar to their desktop counterparts and perform the same functions, but are miniaturized and
optimized for mobile use and efficient power consumption.
Laptops usually have LCD (liquid crystal displays) . In addition to a built-in keyboard, they may utilize a
touchpad although an external keyboard or mouse can be attached.
USB Flash Memory Drives
There are scores of products out there to help you send, store, and transport your data, but few can match the simplicity
and sheer portability of a tiny USB flash drive. Like an old-school floppy disk re-tailored for the twenty-first century, USB
flash drives offer the capacity of a modest hard drive (up to 128 GB) the portability of a cigarette lighter, and the plugand-play simplicity of a modern peripheral.
These portable devices go by a colourful assortment of names--keychain drives, memory sticks, iDucks and so on - but
they all work pretty much the same way. Plug one into a USB port on your PC and it'll show up like any other hard drive.
Drag and drop your data onto it from your PC at work, pull out the drive, and plug it into your computer at home.
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The iPad
The iPad is a tablet computer developed by Apple. It is smaller than a typical laptop, but significantly
larger than the average smart-phone. The iPad does not include a keyboard or a trackpad, but instead
has a touchscreen interface, which is used to control the device.
Like the iPhone, the iPad runs Apple's iOS operating system. This allows the iPad to run third-party apps,
which can be downloaded from Apple's App Store. While apps designed for the iPhone can also be
installed and run on the iPad, many iOS apps are developed specifically for the iPad. Since the iPad's
screen is much larger than the iPhone's screen, iPad apps can include more user interface features that
would not fit within an iPhone app. Therefore, productivity, graphics, and video-editing apps are often
developed specifically for the iPad rather than the iPhone.
The iPad's 9.7 in screen size also makes it ideal as an e-reader. The iBooks app allows you to download
electronic versions of books from the iBookstore and read them on your iPad. Since the iPad has a full
colour screen, it supports novels as well as art books and illustrated children's stories. Books can be read one page at a time in portrait mode or with pages side by
side in landscape mode. (Ref. Wikipedia)
The iPhone
The iPhone is a smartphone developed by Apple. The iPhone has a sleek, minimalist design, and differs from other smartphones in its lack of buttons. Most
operations on the iPhone are performed using the touch screen display. All versions of the iPhone have a rear-facing camera, but the iPhone 4 introduced a frontfacing camera, which can be used for video calls made using the Face Time feature. The iPhone 4 also includes a 960 x 640 pixel "retina display," which has double
the resolution of previous iPhone displays.
Internally, the iPhone runs the iOS, an operating system developed by Apple for portable
devices. This allows the iPhone to run "apps," or applications developed specifically for the
Phone. Apps can be downloaded from Apple's App Store, which can be accessed
through iTunes or directly from the iPhone's built-in App Store app. There are hundreds of
thousands of apps available from the App Store, which provide the iPhone with limitless
functionality. (Ref. Wikipedia)
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Kindle Fire
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The Kindle Fire is a mini tablet computer version of Amazon's Kindle e-book reader. The Kindle Fire has a colour 7-inch multitouch display and runs a custom version of Google's Android operating system called Fire OS. The device—which includes
access to the Amazon Appstore streaming movies and TV shows, and Kindle's e-books.—was released to consumers. In
September, 2012, upgrades to the device were announced with consumer availability to those European countries with a
localized version of Amazon's website (United Kingdom, France, Germany, Italy and Spain).
The Kindle Fire's external dimensions are 7.5 × 4.7 × 0.45 inches (191 × 119 × 11 mm). The visible area of the screen is 6 × 3.5
inches (152 × 89 mm). Amazon's business strategy is to make money through sales of digital content on the Fire, rather than
through the device itself.
In September 2012, the Kindle Fire was upgraded to the second generation.. A more powerful and video-friendly version,
the Kindle Fire HD (7 and 8.9 inch versions) were also made available. (Ref. Wikipedia)
The Nook
The Nook Simple Touch (also called the Nook Touch) is the second generation of the Nook e-book device by Barnes & Noble. It
features an 800x600 E Ink screen that has a touchscreen using a network of infrared beams slightly above the screen surface. It has
wireless connectivity via Wi-Fi and has a micro USB port for charging and connecting to a computer. In April 2012, Barnes & Noble
introduced a Simple Touch Reader with "GlowLight" technology.
The device can store an estimated 1,000 books; it has 2 GB of internal memory of which only half is available for content. Of the
1 GB of content, 750 MB is reserved for content from Barnes & Noble's e-book store, which leaves approximately 250 MB for other
files. (Ref. Wikipedia)
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iPod
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The iPod is a line of portable media players designed and marketed by Apple Inc. The first line was released on October 23, 2001,
about 8½ months after iTunes (Macintosh version) was released. iTunes is a media player, media library, and mobile device
management application. The most recent iPod redesigns were announced on September 12, 2012. There are four current versions
of the iPod: the ultra-compact iPod Shuffle, the compact iPod Nano, the touchscreen iPod Touch, and the hard drive-based iPod
Classic.
Like other digital music players, iPods can serve as external data storage devices. Storage capacity varies by model, ranging from 2 GB for the iPod Shuffle to
160 GB for the iPod Classic. The devices are controlled by the Samsung ARM and the Apple A5 CPUs.
(Ref. Wikipedia)
Bluetooth
This can be loosely defined as Radio technology that enables devices such as computers, mobile phones and hands-free kits to be connected without cables up to
30 feet away. Bluetooth technology provides complete wireless mobility.
Motorola Bluetooth headset
Car-PC Bluetooth USB Adapter
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Acknowledgements
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In this EBook I have endeavoured to give a brief description of today's computer components and peripherals as well as some popular mobile devices. Even the
dedicated technophobes out there should gain some insight into the wealth of technology available to us today.
I thank you for your patronage.
________________________________________
KENNETH E. MACKIE
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