This command annotates each line in the specified file.txt with the most recent commit hash, author, and timestamp—ignoring whitespace-only changes thanks to the -w flag—so you can see who last modified each line while filtering out formatting-only edits.
When run, git reads the file’s history line by line, attributes each line to a commit, and displays the commit SHA, author name, and date; the -w option tells it to skip over lines that differ only in whitespace so that code moves or reformatting don’t obscure real changes.
You can use -L <start>,<end> to blame only a specific line range, -e to include author email, or -C/-M to follow code movement and file copies. Similar commands include git log -L <range>:<file> for detailed history of a section or git annotate as an alias for blame.