What do the symbols displayed by ls -F mean?

ls -F appends symbols to filenames. These symbols show useful information about files.

• @ means symbolic link (or that the file has extended attributes).
• * means executable.
• = means socket.
• | means named pipe.
• > means door.
• / means directory.

If you want this behavior to be the default, add this to your shell configuration: alias ls='ls -F'.