What does chmod 640 mean? A sample permission string would be chmod 640 file1, which means that the owner has read and write permissions, the group has read permissions, and all other user have no rights to the file.
What does chmod 666 do? chmod 666 file/folder means that all users can read and write but cannot execute the file/folder; chmod 777 file/folder allows all actions for all users; chmod 744 file/folder allows only user (owner) to do all actions; group and other users are allowed only to read.
What does chmod 644 mean? chmod 644 means only the owner are allowed to write/modify, read-only for others (group) included. There is no number 7 or 5 in the chmod number, which means no one are allowed to execute the file.
What does chmod 700 do? chmod 700 file
Protects a file against any access from other users, while the issuing user still has full access.