History of computers Flashcards
First Generation : Vaccumm Tubes (1946)-(1959)
The history of computers is generally divided into four periods or generations, with a fifth poised to emerge. Computer generations are defined by major technological developments that fundamentally changed the way computers operated. Most major developments have resulted in smaller, less expensive, more powerful, and more efficient computing systems. This evolution has been incredibly rapid and continues at a dramatic pace.
Second Generation: Transistors (1959–1965)
As technology continued to evolve, so did computers. Smaller electronic components were able
to maintain the two states of “off” and “on,” and transistors were more reliable and economical than vacuum tubes. It is interesting to note, however, that while transistors were invented in 1947, it took nearly a decade for them to find their place in computer hardware. With transistors generating less heat than the vacuum tubes previously used, overheating became less of a concern. This meant that components would last longer, and there was less risk of the system crashing.
Third Generation: Integrated Circuits (1965–1971)
The invention of integrated circuits enabled the development of computer systems that were
cheaper, faster, smaller, and more reliable. Operating systems made it possible for computers to run multiple applications at the same time and to share memory and other resources. The computational time was reduced from milliseconds to nanoseconds. While integrated circuits increased computing power, they were complicated to manufacture, difficult to maintain, and required air conditioning to keep the computers cool enough to run.
Fourth Generation: Microprocessors (1971–Present)
Microprocessors include thousands of integrated circuits on a single silicon chip. This
generation of computers is characterized by a significant reduction in processor size and at the same time, a significant increase in capabilities. The Intel 4004 chip, developed in 1971, included all the components of the computer on a single chip. The IBM computer for home use was available in 1981, followed by Apple’s Macintosh computer in 1984. Fourth generation computers also saw the development of graphical user interfaces, the mouse, and handheld devices.
Fifth Generation: Artificial Intelligence (Future)
The fifth generation started in the early 1980s when microprocessor chips were able to accommodate tens of millions of electronic components using ultra large-scale integration (ULSI). These systems are capable of running multiple programs concurrently and are based on artificial intelligence (AI). Fifth generation computers will support the development of artificial intelligence and natural language processing while using principles of robotics, neural networks, expert systems, and natural language understanding and generation.
Abacus
The abacus was first used in China and then by the early Greek and Roman civilizations. The abacus consists of strings of beads strung on rods which are mounted on a rectangular frame. As the beads are moved back and forth on the rod, their positions represent stored values. To carry out calculations, the abacus needs a human operator. Thus, the abacus must combine with a human to form a system whose purpose is carrying out additions.
Leibniz Machine
The Leibniz machine was designed to perform basic arithmetic operations, and the algorithm for addition was embedded into the structure of the hardware itself. Babbage’s Analytical Engine (which was never constructed) was designed to read instructions in the form of holes on paper cards. Babbage’s Analytical Engine was programmable. Ada Lovelace, who showed in a publication that the Analytical Engine is indeed programmable, is considered to be the world’s first programmer.
Punched Cards
The idea of communicating instructions with punched cards originated in 1801 in a system specifying the steps of the weaving process. Different patterns of holes resulted in different woven designs. Herman Hollerith used punched cards to speed up the tabulation process in the 1890 US census. Punched cards were heavily used for a variety of computing systems until the mid-1970s.
Electromechanical Machine
Examples of this progress include the electromechanical machine of George Stibitz completed in 1940 at Bell Laboratories and Mark 1 completed in 1944 at Harvard University by Howard Aiken and a team of IBM engineers. These machines made heavy use of electronically controlled mechanical relays.
Fully Electronic Computer
In parallel to electromechanical machine efforts, the use of vacuum tubes gave way to fully electronic computers, such as the Atanasoff-Berry machine constructed at Iowa State College between 1937 and 1941, and Colossus built in England to decode German messages during the latter part of World War 2. Other more flexible machines, such as ENIAC (Electronic Numerical Integrator and Calculator) developed at Pennsylvania State University, soon followed.
Computing System
The development of computer systems largely depended on advancement in technology such as the invention of the transistor. Later the invention of complete circuits allowed for integration of multiple circuits on one piece of semiconductor material such as silicon. These
integrated circuits reduced the size of the early computing systems of the 1940s from room- sized machines, to the size of a single cabinet. Processing power began to double every two years. The mass production of integrated circuits made the computers less expensive and thus readily available in the market.
Desktop Computer
A major step in the popularization of computer systems was the development of desktop computers. Steve Jobs and Stephen Wozniak built the first viable home computer and established Apple Computer, Inc. (now Apple, Inc.) in 1976 to mass-produce their garage-built, home computer. Other companies such as Commodore offered similar solutions, but these smaller computers were not widely adopted by businesses who continued to use the well- established mainframe computers
Personal Computer
In 1981, IBM introduced its first desktop computer called the personal computer, or PC, whose underlying software was developed by a newly formed company known as Microsoft. The term PC is now widely used to refer to all machines that evolved from IBM’s personal computer product, including desktops and laptops.
Internet
Toward the end of the twentieth century, the ability to connect individual computers in a world-wide system called the internet was revolutionizing communication. The British scientist Tim Bernes-Lee proposed a system by which documents stored on computers throughout the internet could be linked together producing a system of linked information called the World Wide Web. In order to make web pages more accessible to users, search engines (i.e. Bing and Google) and browsers (i.e. Edge and Chrome) were developed. Search engines use technologies to index and tag pages so users can quickly search for resources based on keywords.
Hand Held Computers
Tiny computers are embedded in a wide variety of electronic appliances and devices. Because hardware components are continuing to reduce in size, the capabilities of smartphones continue to expand. These hand-held computers are much more than mobile telephones. They are equipped with a wide variety of sensors, including cameras, microphones, compasses, and touch screens, as well as a number of wireless technologies used to communicate with other smartphones and computers.
