mkdir makes or creates a directories on the file system so here it made dir_documents
cp copies files and the directories here it copied file1 to dir_documents
mv it moves files so here i moved file1 to the music folder
rm it deletes files so in this case i removed file1 and dir_ documents
help displays the information about the bulletin commands
man is the manual of Linux but here there was no manual found
whatis displays a short manual page descriptions. so here it displayed bash manual description
alias instructs the shell to replace one string with another when executing commands. So here I put echo bark and came out “bark”