I am having trouble with file permissions. There are tons of websites and other sources regarding this. But none are addressing my issue. When I set a permission on a folder I have with
chmod 660 [name of folder]
The system will restrict outside PCs from having access to the folder. But, if I use
chmod 770 [name of folder]
I can gain access to the folder, download it and delete data from it. Is there something I do not get? I thought that with a "0" in the last digit of the three numbers that it will not let other users or groups alter and gain access to folder. What am I not understanding?