What does chmod 777 mean? Setting 777 permissions to a file or directory means that it will be readable, writable and executable by all users and may pose a huge security risk.
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 400 do? chmod 400 myfile – Gives the user read permission, and removes all other permission. These permissions are specified in octal, the first char is for the user, second for the group and the third is for other.
What does chmod 444 mean? 444 = (r– r– r–): owner/group/others are all only able to read the file. They cannot write to it or execute it.