ls can also list symbolic links;
tosca~$ ls -l /etc/localtime
lrwxrwxrwx 1 root root 36 Apr 10 19:44 /etc/localtime -> /usr/share/zoneinfo/Europe/Amsterdam
rm by default does only remove the symlink, not the file that it is pointing to. However when you read or write to a symbol link, it will write the contents to the file that the symlink points to.
When you remove the target file which the symlink is pointing to, the symlink does not disappear, because the target file does not keep information about which symlinks point to it. You can just remove a symlink that points to a non-existing file.
If you try to read from it, it just says the file does not exist.
symlinks can point to other links, but i believe that there is a limit to the ammount of links they point to.
$ ln -s a b
$ ln -s b a
$ cat a
cat: a: Too many levels of symbolic links
Hope it was helpful