The IBM 701

The History of International Business Machines and IBM Computers

Computer Room With Early IBM Computers
Tom Kelley Archive/ Retrofile/ Getty Images

This chapter in the "History of Modern Computers" finally brings us to a famous name most of you will have heard of. IBM stands for International Business Machines, the largest computer company in the world today. IBM has been responsible for numerous inventions having to do with computers.

IBM - Background

The company incorporated in 1911, starting as a major producer of punch card tabulating machines.

During the 1930s, IBM built a series of calculators (the 600s) based on their punch card processing equipment.

In 1944, IBM co-funded the Mark 1 computer together with Harvard University, the Mark 1 was the first machine to compute long calculations automatically.

The IBM 701 - General Purpose Computer

The year 1953 saw the development of IBM's 701 EDPM, which, according to IBM, was the first commercially successful general-purpose computer. The 701's invention was due in part to the Korean War effort. Inventor, Thomas Johnson Watson Junior wanted to contribute what he called a "defense calculator" to aid in the United Nations' policing of Korea. One obstacle he had to overcome was in convincing his father, Thomas Johnson Watson Senior (IBM's CEO) that the new computer would not harm IBM's profitable punch card processing business. The 701s were incompatible with IBM's punched card processing equipment, a big moneymaker for IBM.

Only nineteen 701s were manufactured (the machine could be rented for $15,000 per month).

The first 701 went to IBM's world headquarters in New York. Three went to atomic research laboratories. Eight went to aircraft companies. Three went to other research facilities. Two went to government agencies, including the first use of a computer by the United States Department of Defense. Two went to the navy and the last machine went to the United States Weather Bureau in early 1955.

Features of the 701

The 1953 built 701 had electrostatic storage tube memory, used magnetic tape to store information, and had binary, fixed-point, single address hardware. The speed of the 701 computers was limited by the speed of its memory; the processing units in the machines were about 10 times faster than the core memory. The 701 also led to the development of the programming language FORTRAN.

The IBM 704

In 1956, a significant upgrade to the 701 appeared. The IBM 704 was considered an early super-computer and the first machine to incorporate floating-point hardware. The 704 used magnetic core memory that was faster and more reliable than the magnetic drum storage found in the 701.

The IBM 7090

Also part of the 700 series, the IBM 7090 was the first commercial transistorized computer. Built in 1960, the 7090 computer was the fastest computer in the world. IBM dominated the mainframe and minicomputer market for the next two decades with its 700 series.

The IBM 650

After releasing the 700 series, IBM built the 650 EDPM, a computer compatible with its earlier 600 calculator series. The 650 used the same card processing peripherals as the earlier calculators, starting the trend for loyal customers to upgrade.
The 650s were IBM's first mass-produced computers (universities were offered a 60% discount).


In 1981, IBM created its first personal home-use computer called the IBM PC, another milestone in computer history.

Next Chapter > John Backus and IBM's FORTRAN