This command is used to uncover who modified certain parts of a file in a git repository by showing the detailed author and revision information for the specified lines in the file.
The -L flag followed by a range <start, end> allows to restrict the output to the given lines range in the file. By default, the line numbers are interpreted as absolute line numbers.
You may as well specify the <start> and <end> parameters according to patterns. Each line numbers or pattern is separated by a comma. Note that end line number is optional. If not provided, this command will consider from start to the end of the file.
Example:
git blame -L 10,20 file.txt