In computer architecture, 1-bit integers or other data units are those that are 1 bit wide. Also, 1-bit central processing unit (CPU) and arithmetic logic unit (ALU) architectures are those that are based on registers of that size.

A one-instruction set computer (OISC), sometimes referred to as an ultimate reduced instruction set computer (URISC), is an abstract machine that uses only one instruction – obviating the need for a machine language opcode. With a judicious choice for the single instruction and given arbitrarily many resources, an OISC is capable of being a universal computer in the same manner as traditional computers that have multiple instructions. OISCs have been recommended as aids in teaching computer architecture and have been used as computational models in structural computing research. The first carbon nanotube computer is a 1-bit one-instruction set computer.