Diff

Text diff compares two text versions and highlights differences. It shows added lines (green), removed lines (red), and unchanged lines, helping track changes between versions.

Common formats include unified diff (most popular, shows context), side-by-side diff (displays texts in parallel), and inline diff (highlights character-level changes).

Lines starting with + are additions, - are deletions, and no prefix are unchanged. Numbers like @@ -1,3 +1,4 @@ show line ranges in old and new versions.