Employed by the ancient Egyptians, Greeks, and Mesopotamians, the earliest calculating devices were systems of writing that used shorthand to denote specific and often large quantities. These written forms differed between cultures but usually involved groups of lines representing single units, with modified characters for intervals of five or ten.

Counting sticks, knots, and tally sticks - with values denoted by specific notches - were common forms of counting and numerical record-keeping throughout the world. These systems, along with the use of Roman numerals, persisted through the Renaissance, as many were hesitant to adopt the Hindu-Arabic numerals used today out of concern for accuracy and the potential for forgery.

The abacus is perhaps the most well known pre-modern calculating device, and is often associated with the wire-and-bead devices that originated in the Middle East. While its true origins remain debatable, the word abacus would have referred to an ancient practice of moving pebbles ('calculi') along lines written in sand.

A common abacus today is the Japanese 'soroban', which has one 'heavenly' bead per wire representing 5, and four 'earthly' beads representing 1 each. This is a simplification of the Chinese 'Suanpan', in which more beads per wire can accommodate other decimal systems such as duodecimal (i.e. base 12, rather than base 10) (Image 1, above).