Intro To 'cat' Command In Linux

2023-04-28 - By Robert Elder

     I use the 'cat' command to read the contents of multiple files at once:

cat file1.txt file2.txt file3.txt

     I can type one or more file names after the cat command, and the contents of these files will be printed one after another on the terminal.  For example, let's first create two files that contain lists of names.  In the file 'names1.txt', we'll put:

Branden McKenna
Verity Jayda
Christopher Rene
Justy Kaiden

     and in the file 'names2.txt' we'll put:

Triston Issy
Ralphie Birdie
Alec Jacqueline

     I can use the cat command to print out each file individually, or I can use it to print out both files together:

cat names1.txt

     Outputs:

Branden McKenna
Verity Jayda
Christopher Rene
Justy Kaiden

cat names2.txt

     Outputs:

Triston Issy
Ralphie Birdie
Alec Jacqueline

cat names1.txt names2.txt

     Outputs:

Branden McKenna
Verity Jayda
Christopher Rene
Justy Kaiden
Triston Issy
Ralphie Birdie
Alec Jacqueline

     I can also use the 'cat' command to print out all of the lines in both files and pipe them into the sort command to have them sorted alphabetically:

cat names1.txt names2.txt | sort

     Outputs:

Alec Jacqueline
Branden McKenna
Christopher Rene
Justy Kaiden
Ralphie Birdie
Triston Issy
Verity Jayda

     And that's why the 'cat' command is my favorite Linux command.