What Does ‘l’ Mean in an ls Listing?

The number of 1kB blocks used by the files in the directory, non-recursively.

Use ls -lh to have some more meaningful output.

The l you're referencing means the file is a link (symbolic) to another file (or directory).

Example

lrwxrwxrwx.   1 root root   22 Feb 24 17:36 jcmd -> /etc/alternatives/jcmd
lrwxrwxrwx.   1 root root   23 Feb 24 17:36 javap -> /etc/alternatives/javap
lrwxrwxrwx.   1 root root   23 Feb 24 17:36 javah -> /etc/alternatives/javah

These were created with a command, ln -s source link. The source is the file/directory we want to link to, the "link" is the name we want to give the link.

making a link

$ ln -s ~/winfile.txt a_link.txt

confirming

$ ls -l | grep winfile
lrwxrwxrwx.   1 saml saml   22 Mar  5 11:15 a_link.txt -> /home/saml/winfile.txt
-rw-rw-r--.   1 saml saml   41 Mar  5 07:44 winfile.txt

Further details

If you consult the info ls info page you'll find descriptions of all the symbols used in the output of ls.

excerpt

 The file type is one of the following characters:

 '-'          regular file
 'b'          block special file
 'c'          character special file
 'C'          high performance ("contiguous data") file
 'd'          directory
 'D'          door (Solaris 2.5 and up)
 'l'          symbolic link
 'M'          off-line ("migrated") file (Cray DMF)
 'n'          network special file (HP-UX)
 'p'          FIFO (named pipe)
 'P'          port (Solaris 10 and up)
 's'          socket
 '?'          some other file type

References

10.1.2 What information is listed - coreutils documentation on ls