The cat (concatenate) command in Linux is used to display, create, merge, copy, concatenate, and manipulate text files. It can read the contents of one or multiple files and print their content as output to the terminal.

Syntax for cat command

The syntax for cat command is:

cat [option] [filename]

Using cat command

To get help with the cat command and know the options available for the cat command, use cat --help

cat --help

Display the contents of a single file

Use cat command followed by txt filename to display the content of the given text file.

syntax: cat txt_filename
Here cat programbr.txt display the content of programbr.txt as output.

cat programbr.txt

cat command with -n option displays the file content in a numbered list with all lines, including blank lines.

Syntax: cat -n txt_filename

Here cat -n programbr.txt displays the contents of programbr.txt in a numbered list

cat -n programbr.txt

Display the contents of Multiple file

cat command can be also used to display the contents of multiple files.

Syntax: cat txt_file1 txt_file2 txt_file3 .....

Here cat programbr.txt programbr2.txt displays the file content of programbr.txt and programbr2.txt

cat programbr.txt programbr2.txt

cat -n programbr.txt programbr2.txt

cat > newfile.txt

cat newfile.txt > newfilecopy.txt

cat -s programbr1.txt

cat programbr.txt >> programbr2.txt

cat -E programbr2.txt

tac programbr.txt

cat /proc/cpuinfo