The file type indicator in Ubuntu "ls -l" command output

The first field of the output of "ls -l" is a string of 10 character that looks like this

drwxr-xr-x

This first character indicates file type. The common indicators are:

- : a plain file

d: a directory

l: a symbolic link

c: a character device, such as /dev/tty0

b: a block device, such as /dev/sda