Technical Diving is a vague term but if you think it's techy then go ahead and post
Technical diving configurations and terminology can be bewildering at times. The same questions do get asked as people get involved in this area. Have a search here first for a query.
Decompression diving allows new depths to be explored, or extended bottom times, both allow the diver to push the boundaries. However, it is not without risk nor is it precise.
Some people say this is madness, other say it is the best diving out there. Either way there are challenges. Look in here if you want to know more about being an underwater Gollum...
There are plenty who move from 'recreational' diving to Commercial diving. It isn't as simple as you might think but the rewards can be there. Post here if this sort of diving interests you.