Viewing & Editing Files

cat file dumps a whole file's contents to the screen — fine for short files, unwieldy for long ones. less file opens a scrollable, searchable viewer for longer files.

Example: choosing the right tool for the file's size

$ cat README.txt
$ less deploy.log
$ nano README.txt

Use cat for something short enough to fit on one screen; switch to less the moment a file is longer than that — it lets you scroll and search (press / then type to search, q to quit) without flooding your terminal with hundreds of lines at once. nano opens a simple in-terminal text editor for quick edits, when a full IDE is overkill or simply unavailable, as is often the case when connected to a remote server.