Bytecode is a set of instructions written in machine readable format for interpreters. Bytecodes are represented as compact numeric codes, constants, and references (normally numeric addresses) that encode the result of compiler parsing and performing semantic analysis of things like type, scope, and nesting depths of program objects.
Bytecode works as do other forms of software instruction sets, by executing orders in a step by step manner.
Bytecode is also known as “p-code” or portable code; it gets its name & nickname for the following two reasons:
1) Because of its processing size (bytes)
2) Because bytecode is only to be executed by machines (machine readable), it can be processed by hardware and virtual machines (making it portable).