The Sinclair Executive was the world's first "slimline" pocket calculator, and the first to be produced by Clive Sinclair's company Sinclair Radionics. Introduced in 1972, the calculator was produced in at least two versions with different keyboard markings; a variant called the Sinclair Executive Memory was introduced in 1973.
Sinclair Executive Type 1
An electronic calculator is typically a portable electronic device used to perform calculations, ranging from basic arithmetic to complex mathematics.
An electronic pocket calculator with a seven-segment liquid-crystal display (LCD) that can perform arithmetic operations
Scientific calculator displays of fractions and decimal equivalents
The interior of a Casio FX-991s calculator
An office calculating machine with a paper printer