A Brief History

In today’s society it is incredibly difficult to imagine life without cell phones and tablets, much less the technology that preceded these advancements and led to today’s personal computer. In today’s day, when kindergarten-aged children have iPhones and children turn to Wikipedia before they would even consider opening an encyclopedia, the question of where the technology came from isn’t asked about, just taken for granted.

The term ‘generation’ is used to describe a period of time between two recent technological advances in the computer technology realm. Each generation that will be discussed on this site is branded by a major technological development which essentially and fundamentally changed the way computers function. These developments often result in increasingly powerful, smaller, inexpensive, and thoroughly more efficient and reliable computing devices. 

This page is mainly dedicated to the past 60+ years (and Four Generations) in which the technology for personal computers has taken off. But it needs to be stated that there were a number of technological and mathematical advances prior to the first electrical computer (which we will talk about on the next page), that led to the present day, fourth generation computer.

Frenchman, Blaise Pascal created one of the first mechanical calculators in 1642, while still a teenager. The machine that ended up being coined the “Pascaline” was a device that could add and subtract two numbers directly and multiply and divide by repetition. Pascal had seen his father, a tax commissioner, struggle with a tedious amount of work and intended to create a machine that could reduce some of the workload.

A Pascaline, signed by Pascal in 1652

After Pascal’s death, Gottfried Liebniz began to work on a calculator of his own.  Liebniz tried to create a machine that could automatically multiply while atop the Pascaline, assuming (incorrectly) that all the dials on Pascal’s calculator could be operated at the same time. Although it was unable to be done, this was the first time a pinwheel was described or used in the implementation of a calculator. He later devised another design, the Stepped Reckoner, which was intended to execute additions, subtractions and multiplications automatically and division under operator control. Liebniz struggled to perfect this design for forty years. He produced two machines; one in 1694 and one in 1706. The only machine known to exist is the one that was created in 1694.

Stepped Reckoner mechanism with the housing removed

Charles Babbage, known as the “Father of Computers,” designed the Analytical Engine in 1837, after designing the Difference Engine (a design for a mechanical computer). The input was to be provided to the machine via punched cards, for output the machine would have a printer, curve plotter and bell.

Analytical Engine

The input/output technology that Babbage utilized was developed further by Harman Hollerith (the founder of the current company IBM), in 1889.

The Harvard Mark-I was created by Howard Aiken, originally presented to IBM in 1937. This was Aiken’s first fully functional computer, it was an all-purpose electro-mechanical computer that was used in the war effort during the last part of World War II. The machine was massive, longer than 50 feet, weighed more than 5 tons, and was made up of over 750,000 parts, it was largely mechanical. For input and output it used three paper-tape readers, two card readers, a card punch, and two typewriters. The machine had a fifty-foot long camshaft that synchronized the machine’s thousands of component parts. The Mark-1 was used to produce mathematical tables but was soon superseded by stored program computers. Adding two numbers took three-six seconds. Aiken developed three more machines (Mark II-IV) and is credited with creating the first fully automatic large-scale calculator.

Harvard Mark-I