Computing · 1961

Time-sharing

Many users at once, each feeling they own the computer.

MIT's Compatible Time-Sharing System, led by Fernando Corbató, rapidly switched one IBM 709 among several terminals. It introduced interactive computing, passwords and online files.

See it in the living tree Wikipedia

Arcs above join it to what it stood on, arcs below to what it led to. The bar places this stretch on the tree's whole timeline.

What it built on 2

FORTRAN 1957
Magnetic-core memory 1953

What it led to 5

Virtual machines 1967
The Mother of All Demos 1968
ARPANET 1969
Unix 1969
Email 1971

Related measurements

The dashed line marks when it first worked.

Computation per constant dollar, 1850-2006 Latest: 7.3B million units of computer power per 2006 $ (2003) Source: Nordhaus 2007, Two Centuries of Productivity Growth in Computing, J. Econ. Hist. 67(1), Table 6

Fastest computer in the world Latest: 2.2×10¹⁸ operations per second (2026) Source: Wikipedia: List of fastest computers; Wikipedia: History of supercomputing