It will only give you the code numbers by having you count the flashes. It'* basically the paperclip with a fancy plastic handle. The book that comes with it will somewhat explain the codes, but so will Google. If you need anything more in depth you will probably need a shop to run it on their analyzer equipment.
I'm pretty much just a novice working on my own cars but pull a lot of info off the net for the codes and in most cases either can fix the problem or at least know what I'm talking about if I need to take it into a shop. I cringe every time I need to leave my vehicle in the hands of a tech that in many cases isn't any more competent than me or is just plain sloppy (i.e scratches, loose bolts/screws, heat shields tossed out, etc.) Half my current tool collection is from what was left in my engine bay from the shop. Sad but true. There a lot of excellent Techs out there who truly care, but in my personal experience they represent the minority within the profession. No offense intended to anyone, just my own personal experience.