Diff

How the diff is computed

This tool finds the longest common subsequence of lines between the two inputs, then emits add/remove operations against it. The result is the same algorithm used by classic Unix diff in line mode — fast for inputs of a few thousand lines and easy to reason about.

For more sophisticated comparisons (word-level highlighting, semantic merges, three-way merges), use a dedicated tool like git diff --word-diff, meld, or delta.