A compiler is software that converts:

Concept

A compiler is a language-processing program.

It analyzes a source program written in a high-level language and translates it into an equivalent target program, commonly machine or object code.

Application

Here the input is programmer-oriented high-level source code, and the output is machine-oriented code that a processor can execute after the normal build stages.

Contrast

• characters to bits: character encoding represents symbols as numeric codes; it is not source-program translation.

• machine language to high-level language: this is the reverse direction associated with decompilation.

• words to bits: this concerns data representation or encoding, not translation of a program.

Cross-check

Tracing the language-processing flow gives source program → compiler → target program, so the direction is from a high-level language to machine language.

Result

Therefore, the required conversion is high-level language to machine language.