PS you mean http://tinyurl.com/hmtm to be http://tinyurl.com/htm ,
right?

No. TinyURL abbreviates long URLs into four-letter codes.

For example, the URL used by Google to let me post this message is:

http://posting.google.com/post?cmd=p...m% 26rnum%3D4

Feeding that mess into TinyURL resulted in the creation of this
shortcut:

http://tinyurl.com/i0b6