Permissions

add write access to current permissions for a file	chmod g+w filename
remove all access for this directory and subdirectories	chmod -r go-rwx *
remove write access from everyone but you	chmod go-w filename
replace current permissions for a file with those specifiedu=user, g=group, o=othersr=read, w=write, x=execute	chmod u=rwx,g=rwx,o=rwx filename
change group associated with files	chgrp newgroup filename
add all permissions for everyone	chmod 777 filename
change ownership of files	chown newowner filename