cat : Displays files on standard output. Two or more files can be specified and output redirected to merge them together.
chgrp : Changes group ownership of a file.
chmod : Changes permissions of a file.
chown : Changes ownership of a file.
cp : Copies a file.
echo : Echoes the text you enter on the screen. Although this isn’t technically a file command, it can be used with redirection to create or add text to a file.
head : Displays the first few lines of a text file.
less : Displays a file a page at a time.
ln : Creates links to files.
ls : Displays files in a directory, as described earlier.
mkdir : Creates a new directory.
mv : Moves or renames a file.
pwd : Prints the name of the current working directory.
rm : Removes a file.
rmdir : Removes a directory.
tail : Displays the last few lines of a text file.
wc : Counts characters, words, and lines in a text file.