A Brief History of Digital Computers
Computers were born out of the need for solving huge number-crunching problems. Before the advent of computers, counting census results would take many years. Today, the same can be done in a fraction of that time. At the start, the computers were so huge that they filled rooms. Now even handheld smartphones have the capability to compute or carry out complex tasks. In 1801, when the Jacquard loom was invented, it used the punching card system. Later, the same system would be used in the earliest computers. In 1922, Charles Babbage conceptualized the first mechanical computer to compute tables. He originated the idea of the programmable computer which was fed input using punch cards and its output was read through a printer, plotter, etc. During the first half of the 19th century, many analog computers were designed, which was very useful for complex computing purposes.
In 1936, Alan Turing conceptualized a universal computing machine that could do all kinds of computations. Modern-day digital computers are built on this model. Soon electromechanical analog computers were designed with electrical switches and mechanical relays. The speed of these machines was greater than mechanical machines, which used only mechanical elements. Next was the development of electric computers. The ENAIC (Electronic Numerical Integrator and Computer) was designed by two University of Pennsylvania professors, John Mauchly and J. Presper Eckert. ENIAC is considered the first electronic programmable computer built in the US and is thought to be the grandfather of modern-day computers. It was much faster, more flexible than earlier computers. Every program had to be mechanically set into the machine by manually setting and resetting switches. It had the advantage of the high speed of electronic components and could be programmed for many complex problems. All these reasons allowed it to add or subtract 5000 times in a second! It had modules for performing square root, multiplication, and division. This machine was so big that it filled a 20-foot*40-foot room and was constructed with over 18,000 vacuum tubes and large numbers of capacitors, inductors, and resistors. Later Maucher and Presper designed the UNIVAC. It was the first commercial computer to be used in businesses and government offices.
Since early machines didn’t store programs they had to be rewired each time reducing their efficiency and capability. The Manchester baby is considered to be the first stored-program computer. In 1947, the first transistor was built by John Bardeen, Walter Brattain under the direction of William Shockley inA Brief History of Modern Day Computers Bell Labs.
From 1955, these transistors replaced the vacuum tubes used in computers. They were smaller, required less power, and gave off less heat. The MOS transistors were developed in 1959. These truly revolutionized the design of digital computers as they were much smaller. The next great technological advance came in the form of the Integrated Circuits. The development of MOS Integrated circuits led to the development of Microprocessors. The Intel 4004 is considered to be the first microprocessor chip. The advances over the past two centuries have resulted in the development of modern-day computers. Today, we all can enjoy the benefit of using super-fast computers with the compact design thanks to the tireless work of so many mathematicians, engineers, and scientists.
The Apple Lisa Computer (1983)
Picture Source: www.mac-history.net
