chmod

Change the access permissions of a file or directory. More information: https://www.gnu.org/software/coreutils/manual/html_node/chmod-invocation.html.

• Give the [u]ser who owns a file the right to e[x]ecute it:

chmod u+x path/to/file

• Give the [u]ser rights to [r]ead and [w]rite to a file/directory:

chmod u+rw path/to/file_or_directory

• Remove e[x]ecutable rights from the [g]roup:

chmod g-x path/to/file

• Give [a]ll users rights to [r]ead and e[x]ecute:

chmod a+rx path/to/file

• Give [o]thers (not in the file owner's group) the same rights as the [g]roup:

chmod o=g path/to/file

• Remove all rights from [o]thers:

chmod o= path/to/file

• Change permissions recursively giving [g]roup and [o]thers the ability to [w]rite:

chmod -R g+w,o+w path/to/directory

• Recursively give [a]ll users [r]ead permissions to files and e[X]ecute permissions to sub-directories within a directory:

chmod -R a+rX path/to/directory