What is "source code"?

Source code refers to the original set of instructions and statements written by a programmer in a programming language. This code is intended to be human-readable and is the foundation that developers use to create software programs. It includes all the functions, procedures, and logic that define how the software operates.

When programmers write source code, they typically use a text editor or an integrated development environment (IDE) to create files that contain these instructions. Compilers and interpreters then transform this source code into machine code that a computer can execute, but the source code itself remains distinct as the initial form of the program.

The other options represent different concepts in software development but do not define source code itself. The compiled version of a program refers to the machine-readable version of the source code. The updated code after a bug fix is a modification of the source code, while the user interface is the visual part of an application that users interact with, rather than the underlying code that makes it function.