Machine code or machine language is a representation of a program in the form of instructions executable by a computer's central processing unit (CPU).

Many compilers, such as C++, convert source code into machine code, which consists of instructions that are recognisable by the CPU of a particular computer.

The contents of machine code are instructions and data that can be executed directly by a computer's central processing unit (CPU). Instructions are patterns of bits, each pattern corresponding to a command to the machine. These instructions are specific to a particular processor, such as the Intel Pentium. Every CPU model has its own instruction set.