- Depending on the security configuration of your Web server the recommended default permissions is:
- 755 for directories
- 644 for files
- Don't use extensions that require 777 permissions!
Note: On file permissions, in general never use 777 if you don't know what you are doing.
Learning the numbers
Each digit corresponds to a group of three letters each digit also corresponds to one set of permissions as follows:
- First digit = owner,
- second digit = group,
- third digit = others (everyone else),
Note: On some servers you may not see the numbers as shown above, what you see is rwxrwxrwx (777) or something similar.
Meaning of the numbers
- 777 means EVERYONE can read, write and execute ANY file.
This something you NEVER want to be allowed on your server/website unless you are absolutely sure you know what you are doing.
- 755 is rwx (owner), r-x (group) and r-x (others) or in other words everyone may read and execute (run) but only the owner(you) may make changes to the file.
- 644 is rw-, r--, r-- or EVERYONE can read the file but only the owner may write to the file.
- These permission can be applied to directories as well which is why you might see this
drwxrwxrwx, the "d" is for directory.
- For a complete explanation read the Wikipedia article: Filesystem permissions