What is a common use of comments in programming?

Using comments in programming is an essential practice that serves primarily to explain code functionality. Comments allow programmers to add descriptive notes within the code, clarifying the purpose of certain sections or specific lines. This is particularly beneficial for enhancing code readability and maintainability, especially when multiple people are working on the same codebase or when the original author revisits the code after some time. By providing contextual information, comments help others (and the original programmer) understand the reasoning behind code decisions, the structure of algorithms, or the intended usage of functions, which reduces confusion and aids in debugging.

In contrast, executing code is the primary role of the code statements themselves and not the comments. While performance enhancement can sometimes be indirectly influenced by clear comments (e.g., by making it easier to optimize code), comments do not improve performance directly. Additionally, defining variables is a syntactical element of programming that involves declaring data storage rather than describing functionality or intent through comments.