Chmod

Chmod is a program that runs on UNIX systems and is made for rights and privileges management. It can be used to change rights and privileges in directories and files.

Examples

https://en.wikipedia.org/wiki/Chmod#Command_line_examples

Sources

http://en.wikipedia.org/wiki/Chmod

https://www.omaserveri.info/nain-muutat-tiedostojen-kayttooikeuksia-linuxissa/ (finnish)