The word “computer” originally referred to a person performing calculations and other operations. In 1822, Charles Babbage, with help from Ada Lovelace, created the difference engine, an automatic computing machine able to deal with polynomial functions and print the results. Babbage’s goal was to eliminate human error by automating the computing process. Due to a lack of funding, this machine never made it beyond developmental stages. In 1837, Babbage developed an idea for the Analytical Engine, another mechanical computer. The Analytical Engine contained an arithmetic logic unit, which is a digital electronic circuit that computes arithmetic and bitwise operations. This machine was of a more general design than the difference machine, and contained the same basic logic structure of modern computers.
 
Konrad Zuse designed and developed the Z1 computer between 1935 and 1938, a programmable mechanical calculator. The machine read instructions off of celluloid film. This machine is considered to be the first programmable computer, and the first modern computer.
 
Alan Turing invented the Turing machine in 1936. This simple model is able to simulate the logic of any computer algorithm. A Turing machine contains a programmable scanner that reads a paper tape, which contains the input and produces the output.
 
In 1943, Tommy Flowers invented the first electric (rather than mechanical) programmable computer. John Vincent Atanasoff and Cliff Berry developed the first digital computer. By1949, computers could run stored programs. In 1942, Konrad Zuse started developing the first commercial computer. He sold it to a mathematician in 1950.
 
In 1960, the Digital Equipment Corporation released the PDP-1, the world’s first minicomputer. In 1968, Hewlett-Packard started producing the HP 9100-A, considered to be the first mass market desktop computer.
 
In 1973, André Truong Trong Thi and Francois Gernelle developed the first microcomputer (Micrel).
 
Ed Roberts, an American computer engineer, founded Micro Instrumentation and Telemetry Systems (MTIS) to build personal rocket kits. However, the company got its big break selling electronic calculator kits. Then, in 1975, the company developed the Altair 8800 computer kit. These computers were first featured in an advertisement in Popular Electronics; individuals could buy the computer kits by mail order. Roberts used the term “personal computers” to describe these kits.
 
The Kenbak-1, a predecessor of the Altair 8800, was first sold in 1971. Only 50 machines were actually built. These computers are considered to be the first personal computers, though that term never took hold until development of the Altair 8800.
 
Released in 1975, the IBM 5100 was one of the first portable computers. It used tape drives for storage. The Osborne I computer, another early portable computer, was released in 1981. It was about half of the weight of the IBM 5100. This computer required a power socket—it had no battery.
 
Steve Wozniak developed Apple I (Apple’s first personal computer) in 1976. This kit came with an operational circuit board; however, users needed to add a power supply and keyboard, among other things, in order to actually operate the machine. Wozniak developed the circuit board, and Ron Wayne wrote the documentation. Steve Jobs handled marketing.
 
IBM released its own first personal computer, the IBM PC, in 1981. “PC” stands for personal computer, but because of the success of the IBM PC, the designation came to signify compatibility with IBM products. Apple products, notably, were not compatible with IBM.
 
The history of personal computers, and of computers in general, is long, complex, and sometimes disputed. But what is the future of personal computers? It seems that cloud computing will have a big effect on personal computers, especially in relation to data processing and storage. Some suggest that personal computers will be able to read human emotions, or at least interact more personally with individual users. Other suggest that computers will be inserted into or operated by the brain.