diff

Compare files and directories. More information: https://man7.org/linux/man-pages/man1/diff.1.html.

• Compare files (lists changes to turn old_file into new_file):
  diff {{old_file}} {{new_file}}
• Compare files, ignoring white spaces:
  diff --ignore-all-space {{old_file}} {{new_file}}
• Compare files, showing the differences side by side:
  diff --side-by-side {{old_file}} {{new_file}}
• Compare files, showing the differences in unified format (as used by git diff):
  diff --unified {{old_file}} {{new_file}}
• Compare directories recursively (shows names for differing files/directories as well as changes made to files):
  diff --recursive {{old_directory}} {{new_directory}}
• Compare directories, only showing the names of files that differ:
  diff --recursive --brief {{old_directory}} {{new_directory}}
• Create a patch file for Git from the differences of two text files, treating nonexistent files as empty:
  diff --text --unified --new-file {{old_file}} {{new_file}} > {{diff.patch}}