In mathematics, an operand is one of the inputs (arguments) of an operator. For instance, in Euclid, detail from The School of Athens by Raphael. ... In mathematics, an operator is a function that performs some sort of operation on a number, variable, or function. ...

3 + 6 = 9

'+' is the operator and '3' and '6' are the operands.

The number of operands of an operator is called its arity. Based on arity, operators are classified as unary, binary, ternary etc. In mathematics and computer programming the arity of a function or an operator is the number of arguments or operands it takes (arity is sometimes referred to as valency, although that actually refers to another meaning of valency in mathematics). ... In mathematics, a unary operation is an operation with only one operand. ... In mathematics, a binary operation, or binary operator, is a calculation involving two input quantities and one kind of a specific operation. ... In mathematics, a ternary operation is any operation of arity three, that is, that takes three arguments. ...

In computer programming languages, the definitions of operator and operand are almost the same as in mathematics. Computer code (HTML with JavaScript) in a tool that uses syntax highlighting (colors) to help the developer see the purpose of each piece of code. ... Programming languages generally have a set of operators that are similar to operators in mathematics: they are somehow special functions. ...

Additionally, in assembly language, an operand is a value (an argument) on which the instruction, named by mnemonic, operates. The operand may be a processor register, a memory address, a literal constant, or a label. A simple example (in the PC architecture) is Assembly language commonly called assembly or asm, is a human-readable notation for the machine language that a specific computer architecture uses. ... In computer science, an instruction typically refers to a single operation of a processor within a computer architecture. ... This article or section does not cite its references or sources. ... In computer architecture, a processor register is a small amount of very fast computer memory used to speed the execution of computer programs by providing quick access to commonly used values—typically, the values being in the midst of a calculation at a given point in time. ... In computer science, a memory address is a unique identifier for a memory location at which a CPU or other device can store a piece of data for later retrieval. ... x86 or 80x86 is the generic name of a microprocessor architecture first developed and manufactured by Intel. ...

MOV   DS, AX

where the value in register operand 'AX' is to be moved into register 'DS'. Depending on the instruction, there may be zero, one, two, or more operands. An instruction set, or instruction set architecture (ISA), describes the aspects of a computer architecture visible to a programmer, including the native datatypes, instructions, registers, addressing modes, memory architecture, interrupt and exception handling, and external I/O (if any). ...