Read A File

The cat command stands for concatenate. Its most common use is to read and display the contents of a file directly in the terminal.

Simply type cat followed by the filename:

cat readme.txt

The contents of the file will be printed to the terminal immediately.

Other useful ways to read files:

head — displays only the first 10 lines of a file:

head readme.txt

tail — displays only the last 10 lines of a file:

tail readme.txt

You can control how many lines to show with the -n option:

head -n 5 readme.txt   # show first 5 lines
tail -n 3 readme.txt   # show last 3 lines

less — opens the file in a scrollable viewer. Press q to quit:

less readme.txt

Note: cat is best for short files. For long files, less is more comfortable to read.