History of Computers: First Generation

• The computer's origin traces back to the 19th century with Charles Babbage.
• Babbage designed the Analytical Engine, serving as the foundation for modern computers.

Five Generations of Computers

• Computers are categorized into five generations, each marking a period of advancement.
• Each generation introduced either a new computer or improvements to existing ones.

First Generation (1937–1946)

• In 1937, Dr. John V. Atanasoff and Clifford Berry created the first electronic digital computer named the Atanasoff-Berry Computer (ABC).
• In 1943, the Colossus, an electronic computer, was built for military purposes.
• The Electronic Numerical Integrator and Computer (ENIAC), was introduced in 1946 as the first general-purpose digital computer.
• ENIAC weighed 30 tons and used 18,000 vacuum tubes for processing.
• ENIAC's power consumption caused lights to dim in Philadelphia when it was turned on.
• Computers of this generation could only perform one task and lacked an operating system.

Second Generation (1947–1962)

• Transistors replaced vacuum tubes, enhancing reliability.
• The Universal Automatic Computer (UNIVAC 1), the first computer for commercial use, was introduced in 1951.
• In 1953, IBM's 650 and 700 series made significant contributions in the computer world.
• Over 100 computer programming languages were developed during this era.
• Computers gained memory and operating systems.
• Storage media like tape and disk were used, along with printers for output.

Third Generation (1963-1975)

• Integrated circuits were incorporated.
• Integrated circuits consist of small silicon wafer chips that contain numerous transistors and circuits.
• Integrated circuits are smaller, cheaper, more reliable, and more powerful which made this generation of computers faster and more powerful.

Fourth Generation (1976-1980)

• Computers utilized Large Scale Integration or Very Large Scale Integration circuits.
• Personal computers became affordable for individuals and companies.

Fifth Generation (1980 – Present)

• Computers feature Ultra Scale Integration of circuits and microprocessors.

First Computers

• The ENIAC (Electrical Numerical Integrator and Calculator) was the first substantial computer by John W. Mauchly and J. Presper Eckert at the University of Pennsylvania.
• ENIAC used 10 decimal digit words instead of binary.
• ENIAC used nearly 18,000 vacuum tubes, surpassing 2,000 vacuum tubes.
• Storage for vacuum tubes and cooling machinery occupied over 167 square meters (1800 square feet).
• ENIAC had punched-card input/output, 1 multiplier, 1 divider-square rooter, and 20 adders using decimal "ring counters".
• ENIAC had quick-access (0.0002 seconds) read-write register storage.
• Executable instructions were embodied in ENIAC's separate units, plugged together to form a route for computations.
• Connections had to be redone for each problem, along with presetting function tables and switches.
• ENIAC was the first successful high-speed electronic digital computer (EDC) and was used productively from 1946 to 1955.
• In 1971, a controversy arose over ENIAC's patentability.
• It was claimed John V. Atanasoff had already used the same ideas in a device built in the 1930s.
• In 1973, the court sided with Atanasoff, acknowledging his deserved recognition.

Progression of Hardware

• In the 1950s two devices were invented that improved the computer field and began the computer revolution.
• The transistor was invented in 1947 by William Shockley, John Bardeen, and Walter Brattain of Bell Labs and began to replace vacuum tubes in computers and electronics.
• The vacuum tube was invented by American physicist Lee De Forest in 1906.
• The vacuum tube worked by using amounts of electricity to heat a filament until it was cherry red which released electrons into the tube that could be controlled within the tube.
• De Forest's original device was a triode, which could control the flow of electrons to a positively charged plate inside the tube.
• An electron current represents one and the absence of one represents zero.
• Vacuum tubes were inefficient, space-consuming, and needed frequent replacement of 18,000 tubes.
• The transistor solved these issues, they had to be soldered together.
• In 1958, Jack St. Clair Kilby of Texas Instruments created the first integrated circuit or chip.
• A chip is a collection of tiny connected transistors through manufacturing, reducing the need for soldering and increasing machine speed.

Mainframes to PCs

• The 1960s saw large mainframe computers become common in large industries with IBM becoming an unquestioned market leader in sales.
• Personal computers exploded in the early 1970s with Steve Jobs and Steve Wozniak exhibiting the first Apple II at the First West Coast Computer Faire in San Francisco.
• The Apple II boasted a built-in BASIC programming language, color graphics, and 4100 character memory.
• The Apple II cost $1298.
• Programs and data could be stored on an audio-cassette recorder.
• Prior to the end of the fair, Wozniak and Jobs had secured 300 orders for the Apple II.
• The TRS-80 was introduced in 1977 manufactured by Tandy Radio Shack.
• The TRS-80 Model II came complete with a 64,000 character memory and a disk drive to store programs and data.
• Only Apple and TRS had machines with disk drives.
• Personal computer applications took off as the floppy disk was a convenient publishing medium for distribution of software.
• IBM produced mainframes and minicomputers for medium to large-sized businesses and started working on the Acorn, which would later be called the IBM PC.
• IBM PC was the first computer designed for the home market that featured modular design.
• Most of the components came from outside of IBM, since building it with IBM parts would have cost too much for the home market.
• When it was introduced, the PC came with a 16,000 character memory, keyboard from an IBM electric typewriter, and a connection for tape cassette player for $1265.
• In 1984, Apple released the first generation Macintosh, which was the first computer to come with a graphical user interface(GUI) and a mouse.
• The GUI made the machine more attractive to home computer users.
• IBM released the 286-AT, which with applications like Lotus 1-2-3, a spreadsheet, and Microsoft Word, quickly became the favourite of business concerns.
• The average computer in someone's home is now more powerful than a machine like ENIAC.
• The computer revolution has been the fastest growing technology in man's history.