Chmod 755 for Directories

The permission 755 is the standard permission for directories on Unix systems, especially for web server document roots and application directories.

Octal breakdown:

• 7 (Owner): read (4) + write (2) + execute (1) = full access
• 5 (Group): read (4) + execute (1) = read and execute
• 5 (Others): read (4) + execute (1) = read and execute

In symbolic notation this is rwxr-xr-x.

For directories, the permission bits have different meanings than for files:

• Read (r): List the directory contents (ls command)
• Write (w): Create, delete, and rename files in the directory
• Execute (x): Traverse into the directory (cd command) and access files by path

Permission 755 allows the owner to create and manage files, while group and others can browse the directory and access its files. The web server needs both read (to list contents for directory indexes) and execute (to traverse into the directory to find requested files) permissions.

Important: Even if a directory is 755, the files inside still need appropriate permissions (typically 644) to be readable. A restrictive directory permission overrides permissive file permissions, but not the other way around.