Generations of computer

Definition of Generation

•  The history of computer development is often referred to in reference to the different generations of computing devices.
•  A generation refers to the state of improvement in the product development process. This term is also used in the different advancements of new computer technology. 
• With each new generation, the circuitry has gotten smaller and more advanced than the previous generation before it. 
• As a result of the miniaturization, speed, power, and computer memory has proportionally increased. 
• Each generation of computers is characterized by major technological development that fundamentally changed the way computers operate, resulting in increasingly smaller, cheaper, more powerful and more efficient and reliable devices. 

First Generation (1940-1956) Vacuum Tubes

The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms. They were very expensive to operate and in addition to using a great deal of electricity, generated a lot of heat, which was often the cause of malfunctions.

Vacuum Tubes

First generation computers relied on machine language, the lowest-level programming language understood by computers, to perform operations, and they could only solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts.

The UNIVAC and ENIAC computers are examples of first-generation computing devices. The UNIVAC was the first commercial computer delivered to a business client, the U.S. Census Bureau in 1951.

Features of First Generation Computers

·        Use of vacuum tubes

·        Big & Clumsy

·        High Electricity Consumption

·        Programming in Mechanical Language

·        Larger AC were needed

·        Lot of electricity failure occured

Second Generation (1956-1963) Transistors

Transistors replaced vacuum tubes and ushered in the second generation of computers. The transistor was invented in 1947 but did not see widespread use in computers until the late 1950s. The transistor was far superior to the vacuum tube, allowing computers to become smaller, faster, cheaper, more energy-efficient and more reliable than their first-generation predecessors. Though the transistor still generated a great deal of heat that subjected the computer to damage, it was a vast improvement over the vacuum tube. Second-generation computers still relied on punched cards for input and printouts for output.

Transistor

Second-generation computers moved from cryptic binary machine language to symbolic, or assembly, languages, which allowed programmers to specify instructions in words. High-level programming languages were also being developed at this time, such as early versions of COBOL and FORTRAN. These were also the first computers that stored their instructions in their memory, which moved from a magnetic drum to magnetic core technology.

The first computers of this generation were developed for the atomic energy industry.

Features of Second Generation Computers

·        Transistors were used

·        Core Memory was developed

·        Faster than First Generation computers

·        First Operating System was developed

·        Programming was in Machine Language & Aseembly Language

·        Magnetic tapes & discs were used

·        Computers became smaller in size than the First Generation computers

·        Computers consumed less heat & consumed less electricity

Third Generation (1964-1971) Integrated Circuits

The development of the integrated circuit was the hallmark of the third generation of computers. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers.

                                                      Integrated Circuits

Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system, which allowed the device to run many different applications at one time with a central program that monitored the memory. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessors.

Features of  Third Generation Computers

·        Integrated circuits developed

·        Power consumption was low

·        SSI & MSI Technology was used

·        High level languages were used

Fourth Generation (1971-Present) Microprocessors

The microprocessor brought the fourth generation of computers, as thousands of integrated circuits were built onto a single silicon chip. What in the first generation filled an entire room could now fit in the palm of the hand. The Intel 4004 chip, developed in 1971, located all the components of the computer—from the central processing unit and memory to input/output controls—on a single chip.

                                      Microprocessor

            As these small computers became more powerful, they could be linked together to form networks, which eventually led to the development of the Internet. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices.

Features of Fourth Generation Computers

·        LSI & VLSI Technology used

·        Development of Portable Computers

·        RAID Technology of data storage

·        Used in virtual reality, multimedia, simulation

·        Computers started in use for Data Communication

Different types of memories with very high accessing speed & storage capacity

Fifth Generation (Present and Beyond) Artificial Intelligence

Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today. The use of parallel processing and superconductors is helping to make artificial intelligence a reality. 

Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come. The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization.

Features of Fifth Generation Computers

·        Used in parallel processing

·        Used superconductors

·        Used in speech recognition

·        Used in intelligent robots

·        Used in artificial intelligence