Computing · c. 500 BCE

Abacus

Beads and counters turn arithmetic into movement you can see and repeat.

Counting boards with loose pebbles spread across Mesopotamia, Greece and Rome, later becoming framed bead abacuses. Skilled users could add and multiply faster than with written numerals, and the device stayed in daily commercial use for over two millennia.

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 1

Numerals and arithmetic 3000 BCE

What it led to 3

Antikythera mechanism 150 BCE
Suanpan 1200
Napier's bones 1617

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