HISTORY OF COMPUTER
TECHNOLOGY
By Sanwal Cheema
OVERVIEW
 The first computer was invented 5 000 years ago. It was called the Abacus.
 Charles Babbage invented the Analytical Engine. The analytical Engine was designed
to make decisions.
 In 1820, Charles Xavier Thomas de Colmar invented the arithmetic, which is a
calculator that could calculate the four basic math functions. After a few improvements, it
was widely used in World War I.
FIRST GENERATION
COMPUTERS
 First generation of modern computers was introduced during World War II
 Colossus was created to decode encrypted Germen messages.
 In the United States, the U.S Army Ordnance Department and the University of
Pennsylvania worked together to develop the Electronic Numerical Integrator and
Computer(ENIAC).
 The ENIAC was developed to calculate ballistic trajectories.
 Eventually the ENIAC gave way to more powerful computers like the EDVAC and
UNIVAC.
SECOND GENERATIONS
COMPUTERS
 Starting in 1956, the second generation computers was marked by the shift from large
bulky, failure-prone vacuum tubes to transistors.
 Transistors use an electrical charge to change the conductive properties of
the transistor itself, allowing it to alternate between an insulator and a
conductor.
 Advances in printers, disk and tapes storage, memory and
stored programs allowed computers to become multifunctional devices!
 In time computer scientists developed high-level languages such as COBOL
(Common Business Oriented Language).
THIRD GENERATION
COMPUTERS
 The integrated circuit (IC), invented independently by Jack Kilby and Robert Noyce in the late
1950s, paved the way for the third generation of computers.
 ICs produced way less heat the transistors. This reduction of heat allows more components to fit on
a single chip.
 A chip is a semi conducted substance (such as silicon),
produced in such a tiny package that it looks like a thin wafer
 These chips have revolutionized computers, allowing them to shrink from the size of a room to the
size of today’s laptop computers, which have more power than their enormous ancestors.
FOURTH GENERATION
COMPUTERS
 The first affordable PC (the MITS Altair 8800), came out in 1974. Soon other
computers were released, such as Apple I and II.
 By 1990, there were over 65 million PC users. 20 years after the introduction of PCs,
there were an estimate of 1 billion PC users worldwide.
 At this time, computer software and hardware was evolving too. GUI (graphical user
interface) operating systems were created.
COMPUTER HARDWARE
AND SOFTWARE
HARDWARE AND
INPUT/OUTPUT DEVICES
 Hardware is a physical piece of equipment for a computer.
 Input devices are devices that send information for the computer
to process.
 Output devices are devices that take processed information from
the computer.
PROCESSORS AND
MEMORY
 The Central Processing Unit acts as the brain of the computer. It
performs all the basic functions.
 Random-access Memory (RAM) is a storage place for data that
goes in and out of the CPU.
HARD DRIVES AND
REMOVABLE STORAGE
 Computers can use many different storage devices, such as CD-ROMs, floppy disks,
and external hard drives.
 8 bits is equal to a byte. 1024 bytes are a kilobyte. 1024 kilobytes are equal to a
megabyte. 1024 megabytes are equal to a gigabyte. 1024 gigabytes is called a terabyte.
 In the American Standard Code of International Interchange, 8 bits is equal to one
letter/character.
NETWORKS
 A network is a way to connect a group of computers together. It can be used to share
files, programs, and other resources.
 There are three common types of network layouts (known as topology). They are:
Bus: All nodes are connected by a single cable.
Star: All computers have their own connection to the central device (hub).
Ring: All nodes are connected in a circle. This has the disadvantage, as if one
breaks down, the circle is broken, which can cause problems.
SOFTWARE APPLICATIONS
 Applications are a type of software that are installed onto your
computer to be able to use.
 They are used to help users perform specific activities.
OPERATING SYSTEMS
 Operating systems are also known as platforms.
 They do jobs such as manage the hardware and software on your PC.
 Operating system manages the information and requests from software and hardware.
 Operating systems also provide an interface, which makes it easier to navigate.
 Some examples of operating systems are Linux, Mac OS, and Windows.