Linux command line 2015
arch
Outputs the processor architecture.
$ arch
i686
cat
Outputs the contents of a file.
$ cat lorem.txt
Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
cd
Change the working directory.
$ cd /bin
chgrp
Change group ownership of files.
$ chgrp games moo.txt
chmod
Change access permissions of files.
$ chmod +x helloworld
chown
Change file owner and group.
# chown root lorem.txt
cksum
Print CRC checksum and byte counts of each file.
$ cksum lorem.txt moo.txt
3570240675 453 lorem.txt
4294967295 0 moo.txt
cp
Copies a file.
$ cp lorem.txt copy_of_lorem.txt