Computing · 1904
Vacuum tube
A glass bulb that could switch and amplify electric current.
John Ambrose Fleming's 1904 diode and Lee de Forest's 1906 triode controlled electron flow in a vacuum. Tubes made radio, television and the first electronic computers possible, switching thousands of times faster than relays.
What it built on 2
What it led to 11
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
US households with a radio Latest: 99 % of households (2005) Source: Our World in Data
Fastest computer in the world Latest: 2.2×10¹⁸ operations per second (2026) Source: Wikipedia: List of fastest computers; Wikipedia: History of supercomputing