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less

An interactive terminal pager.

less reads input or files and lets you navigate them with vim-style keys: forward and backward page, search with / forward and ? backward, jump to specific line numbers, and follow growing files (less +F, similar to tail -f). Unlike more, the older Unix pager that less replaced, less can scroll backwards as well as forwards.

Mark Nudelman has maintained less since 1985. The codebase is remarkably stable; minor improvements arrive each year (better regex support, improved Unicode handling, syntax-highlighting hooks) but the user-facing behaviour has been compatible across decades.

less is the default pager that man, git, info, and many other tools invoke when output is too long to fit on screen. Its configuration through the LESS environment variable lets users tune its behaviour globally — a common configuration is LESS=-R to preserve ANSI colour codes from tools like git or ripgrep. The minimal-keystroke navigation has shaped how a generation of Unix users think about reading text.

Already preinstalled on every Linux and macOS system.