less: view files page by page

Updated November 2026

less shows a file one screen at a time and lets you scroll and search in both directions. It is the default pager for manual pages and the right tool for reading logs. For short files, cat prints everything at once.

Examples

less /var/log/apt/history.log
less -N script.sh            # with line numbers
less -S wide.csv             # do not wrap long lines (scroll sideways with arrows)
less +G app.log              # start at the end
less +F app.log              # follow the file as it grows (like tail -f)
journalctl -b | less         # page through command output
cat notes.txt                # print a short file
cat part1 part2 > whole      # join files
head -n 20 data.csv          # first 20 lines (see tail for the end)

Keys inside less

Useful settings

Set default options in the LESS environment variable, for example in ~/.bashrc:

export LESS='-R -i -M'      # keep colours, smart case search, detailed prompt

-R displays colour codes from commands such as grep --color=always or git log correctly. Compressed logs can be read with zless (see gzip).

cat tips

• cat -n numbers lines; cat -A (GNU) shows tabs as ^I and line ends as $, useful for finding stray spaces or Windows line endings.
• You do not need cat file | grep x: grep x file does the same with one process less.
• tac (GNU) prints a file with the last line first.

more is the older pager, still present on every Unix system. It only scrolls forward on some systems, which is where the name less ("less is more") came from.