history of modern computers

http://campus.udayton.edu/~hume/Computers/comp3.htm

History of Modern Computers

Computing in the Modern WorldMs. Stewart



The evolution of modern computers is divided into a few "distinct" generations.



Each generation is characterized by extreme improvements over the prior era in the technology used in the: manufacturing process, the internal layout of computer systems, and programming languages.


First Generation of Computers

1945-1956 Computers were mainly used by the

government for use in war and designing strategies.

Konrad Zuse (1941) used computers to design airplanes and missiles.

The British designed a computer to decode secret messages (1943).


First Generation of Computers, cont’d.

1945-1956 Aiken created an electronic calculator

(1944) to create charts for the Navy. It was half as long as a football field.

ENIAC computer (1945) was a general purpose computer used to design the hydrogen bomb.


First Generation of Computers, cont’d (2).

1945-1956 Neumann designed the EDVAC computer

(1945), which was able to store a program as well as data. The computer could also be stopped and re-started – a first for this time period.

Key development was the Central Processing Unit (CPU).


First Generation of Computers, cont’d (3).

1945-1956 Eckert and Mauchly developed the

UNIVAC I (1951). It was the first commercially successful computer.


Second Generation Computers 1956 – 1963 The invention of the

transistor greatly changed the computer's development. The transistor replaced the large, cumbersome vacuum tube in televisions, radios and computers.

As a result, the size of electronic machinery has been shrinking ever since.


Second Generation Computers1956 – 1963 Transistors led to second generation

computers that were smaller, faster, more reliable and more energy-efficient than their ancestors.


Second Generation Computers 1956 – 1963 The Stretch by IBM and LARC by Sperry-Rand were

supercomputers developed for atomic energy laboratories and could handle an enormous amount of data.

The machines were costly, however, and tended to be too powerful for the business sector's computing needs, thereby limiting their attractiveness.


Second Generation Computers1956 – 1963 Throughout the early 1960's, there

were a number of commercially successful second generation computers used in businesses, universities, and government.


Second Generation Computers1956 – 1963 They contained all the components

we associate with the modern day computer: printers, tape storage, disk storage, memory, and stored programs.

An example was the IBM 1401.


Second Generation Computers1956 – 1963 It was the stored program and

programming language that gave computers the flexibility to finally be cost effective and productive for business use.


Second Generation Computers 1956 – 1963 The stored program concept meant that instructions

to run a computer for a specific function (known as a program) were held inside the computer's memory, and could quickly be replaced by a different set of instructions for a different function. For example, print one minute, then design documents

the next.


Second Generation Computers 1956 – 1963 More sophisticated high-level languages such as

COBOL (Common Business-Oriented Language) and FORTRAN (Formula Translator) came into common use during this time, and have expanded to the current day.

These languages replaced cryptic binary machine code with words, sentences, and mathematical formulas, making it much easier to program a computer.


Second Generation Computers1956 – 1963 New types of careers (programmer,

analyst, and computer systems expert) and the entire software industry began with second generation computers.


Third Generation Computers

1964 – 1971 Transistors, when first created,

generated massive amounts of heat. Kilby (1958) developed an integrated circuit to use in the place of transistors.



1964 – 1971 The IC combined three electronic components onto

a small silicon disc, which was made from quartz. Scientists later managed to fit even more

components on a single chip, called a semiconductor.

As a result, computers became ever smaller as more components were squeezed onto the chip.



1964 – 1971 Another development was

the use of an operating system that allowed machines to run many different programs at once with a central program that monitored and coordinated the computer's memory.

Operating Systems (examples) Windows Vista MAC

Programs (examples) Word Excel Access PowerPoint Windows Media Player Skype


Third Generation Computers Thompson and Ritchie (1969)

developed the UNIX operating system. UNIX was the first modern operating system that provided a sound intermediary between software and hardware.


Fourth Generation Computers 1971 – present The next step in the computer

design process was to reduce the overall size.

Hundreds of thousands of components were squeezed onto a chip.

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