In computer programming, a comment is a piece of text within a program's source code that is intended to be read by humans and is ignored by the compiler or interpreter. Comments are used to explain what the code is doing, making it easier to understand and maintain. They can describe the overall purpose of a function, specify why a certain approach was taken, or provide any other relevant information. Comments are essential for collaborative development and future code revisions, as they help other programmers (or the original author) understand the logic and purpose behind specific sections of code.