What is what does diff mean?

Diff means "difference" or "to compare two files line by line" in computing and programming. The Unix command 'diff' is used to compare the content of two files and display their differences. The output of the diff command highlights the unique changes in the two files using special symbols and notation. Many text editors also incorporate diff functionality to highlight the differences between two versions of a file or document. Diff can be helpful in identifying discrepancies between code versions, tracking changes made by multiple users, and identifying and reconciling conflicts between versions of the same file.