cat - concatenate files to stdout
$ cat [file...]
This program passes contents of specified files to standard output, in the specified order. If no file is specified, or it is -, it defaults to standard input.
file: Files to print# Display a single file $ cat README.md # Minerva Graphical Unix-like operating system for x86 computers. ... # Display standard input $ cat aaa aaa bbb bbb^C # Display ls output where each file is in separate line $ ls | cat Desktop Documents Downloads README.md Source js-tests tests web-tests # Display multiple files $ echo 123 > test.txt $ echo 456 > test2.txt cat test.txt test2.txt 123 456