Chapter 2
The Computer
• Cell phones off and put away.
• Wireless turned off on laptop
or tablet.
• Your Technology Agreement
says: do not check cell
phones during class, and,
use technology only for
taking notes.
Binary Numbers
“One if by land, and two if by sea…”
-Henry Wadsworth Longfellow
This classic line illustrates the
usefulness of a binary code for
communicating a message.
Morse Code (an early binary system)
The telegraph key was once used to encode messages in Morse
code, an early system of binary transmission.
→Take note of the dots and dashes.
Early Computers
• Computers once
required massive
amounts of space.
• The 1946 Electronic
Numerical Integrator
and Calculator
(ENIAC) weighed
30 tons!
Microsoft begins…
Microsoft got its start by developing software for the Altair
8800 computer in 1975.
The MITS Altair was sold as a kit, and had no keyboard,
no monitor. The user flipped switches to program it.
Tablets vs. Desktops
• Alan Kay created this prototype tablet computer in 1968—more
than 40 years ago! (left)
• The Alto PC was the first desktop PC with a graphical user
interface & mouse – from Xerox, in1973. (right) Note the ‘page’
is ‘page-like’ view.
Inside the Computer
A computer is a
carefully engineered
collection of individual
components:
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•
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Motherboard
Power supply
CPU
Video card
RAM
Hard drive
Optical drive
Network card
The CPU
• Don’t be fooled by its small
size!
• The CPU (central
processing unit) contains
millions of transistors and
acts as the brain of the
computer.
Moore’s Law
In 1965, Intel cofounder, Gordon Moore, predicted that the number
of transistors per square inch on integrated circuits (the predecessor
of the microprocessor) would double about every two years for the
foreseeable future.
The RAM chip
• A RAM chip is carefully
inserted into a
designated slot on the
computer’s motherboard.
• RAM is a type of volatile
memory. It is used to
temporarily store
operating system
software and program
files while a computer is
running. (random
access memory)
Video Card
• A video card
generates the digital
image displayed on a
computer monitor or
screen.
• The video signal is
fed to a computer
monitor via an output
connector on the
outside of the box.
• Older cards had
analog video out.
Evolution of the Mouse
A) Original prototype
invented in 1963
B) First commercial
3-button mouse
C) Modern wireless
mouse
D) Will the mouse
become obsolete?
Apple Markets the GUI…
• This 1983 marketing piece highlights Lisa’s user-friendly
graphical user interface (GUI).
• Why did the Lisa fail?
The Keyboard
The QWERTY layout
dates back to the 1800s
and is still used today on
computer keyboards.
1. Character Keys
The character keys are used
to insert letters, numbers,
and punctuation symbols into
a document or text-box
window.
• Letters, numbers, punctuation, & symbols
• Space Bar
• Return/Enter
• Backspace/Delete
2. Modifier Keys
Modifier keys are used to alter the actions of other keys.
• Shift
• Control/Command
• Alt/Option
• Escape
3. Function Keys
Function keys are dedicated to performing specific tasks.
• F-keys
• Home/End
• Page Up/Page Down
• Arrow Keys
File System Browser
The file system browser of a computer functions virtually the same,
regardless of whether you are using a PC or a Mac.
•On a PC, Windows Explorer is used to access and manage applications,
folders, and files.
•On a Mac, the Finder application performs many of the same functions.
Advanced Searchability
The file system browser gives users many options for
conducting advanced searches.
Data Storage
• Text consumes a small amount of digital real estate
• Computer graphics, digital images, sound, and video
gobble up precious drive and storage space.
File Management 101
• A structural hierarchy is formed
by nesting—the act of placing
one folder inside another and
so on.
• The folder at the top of a
nested collection of subfolders
is called the root or parent
folder.
Digital Storage Solutions
The term storage is used to describe any number of devices
that can be used to permanently record and store digital
information.
Three types:
1. Fixed storage or direct-attached storage (DAS)
2. Removable storage
3. Network-attached storage (NAS)
1. How does cloud computing compare to NAS?
Hard Drive
• The most common type of
fixed storage medium is a
hard-disk drive (HDD or hard
drive).
• It reads and writes data onto
magnetically charged
spinning platters located
within a sealed compartment.
• Note the stylus and moving
parts.
Internal & External Drives
• Internal hard drives store the operating system and software application
files installed on the computer.
• External hard drives are designed to sit outside of the box and must be
physically connected to the computer with a serial interface cable.
Hard Drive Capacity
The capacity of a hard drive is rated
according to how much data it can hold
(in gigabytes, terabytes, etc.).
•kilobyte (KB) = 210 or 1,024 bytes
•megabyte (MB) = 220 1,048,576 bytes
•gigabyte (GB) = 230 or 1,073,741,824 bytes
•terabyte (TB) = 240 or 1,099,511,627,776 bytes
•petabyte (PB) = 250 or 1,125,899,906,842,624
•exabyte (EB) = 260 or 1,152,921,504,606,846,976 bytes
Solid-State Drives (SSD)
SSD drives are:
•Durable (no moving parts)
•Allow faster access
•Allow the computer to boot
faster
•Still a more expensive
option for high capacity
internal storage.
•They slow down as they fill
up and can be expensive.
Optical Discs
• Optical storage devices
use a laser beam to read
and encode data onto the
reflective inner surface of a
hard plastic disk.
• What is the likely future of
optical storage? Why?
Types of Discs
• CD-ROM: storage capacity of 486 floppy disks
• DVD: capacity is roughly 6x that of a CD
• Blu-ray: permits distribution of HD video content (Sony
proprietary system)
Ever see a floppy disk?
• Each of the 3.5-inch
floppy disks pictured
(left) had a capacity of
1.44 MB.
• Original ‘hard plastic’
ones were 400k, then
800k.
• MS Word 1.0
• It would take 2,845 of
these disks to equal the
capacity of a 4GB SD
memory card (roughly
the size of a thumbnail).
Cloud Storage
Cloud storage
enables multiple
users to
collaborate on the
development of a
single document
or body of work.
Connector Cables
USB (1.0, 2.0, and 3.0) and IEEE 1394b (Firewire 800) are two
of the most common protocols used today for connecting an
external device to a computer.
• Some quiz and test
review…
Bill Gates and Paul Allen are known as
founders of what company?
Microsoft
QWERTY keyboards originated in what
decade?
1880s
iLink is a term used by what company,
to refer to what kind of connection,
developed originally by what
company?
Sony, firewire,
Apple
The term PC is a generic reference to
any computer running the ---operating system.
Windows
A string of eight 0s or 1s is called a
________.
byte
The invention of the_____ in 1971,
was a major technology advancement
that made possible the development
of the personal computer.
microprocessor
The _______________ serves as the
brain of the computer.
CPU
A certain computer is advertised as
having a 2.7 GHz processor, referring
to the _______________.
The number of
instructions that can
be processed per
second by the CPU
For more than 40 years, the concept
call ______ has successfully predicted
the doubling of transistors on an
integrated circuit every two years.
Moore’s Law
A hard disk drive relies on
_________________ for data storage.
Non volatile
memory
The first GUI was developed by
_________ in the early 1970s. GUI
stands for ________.
Zerox, at Xerox
PARC, graphical
user interface
A terabyte is roughly ____ bytes,
while a A kilobyte is roughly _____
bytes.
One trillion, one
thousand
LAN stands for ---- and GUI stands for
Local area
network,
graphical user
interface
IP, as in IP address, stands for --------.
Internet
Protocol
------ authorizes domain name
registrars, through which domain
names are registered and reassigned,
and oversees the domain name system
of the Internet.
ICANN, Internet
Corporation for
Assigned Names
and Numbers
ICANN authorizes _______, like
GoDaddy, to license the use of a
particular domain name to an
individual or entity
Registrars
Chap 3 -- A ________________ is a full-size
layout of a visual design developed for the
purpose of refining or testing a concept.
Mock up
A _____ is a simple visual
representation of the layout or
skeletal structure of a multimedia
page or interface.
wireframe
The process of evaluating and refining
a multimedia product (prior to a
public release) by soliciting feedback
from a sample population of users is
called ____.
Usability testing
A __________ is a paper or working
model of the project designed for
simulation and testing.
prototype
A ________ combines words and
pictures to communicate an idea.
Resembles a comic book
Made up of a series of boxlike frames
depicting the visual portion of a TV or
film production or a visual story.
storyboard
The protocol that was developed to
allow original independent LANs to
communicate with each other, leading
to introduction of the Internet as an
evolution of the Arpanet.
TCP/IP