Salvage title means the bike has been written off by an insurer. Sometimes that's simply because the cost to replace the plastic body panels was more than some % of the total value of the overall vehicle (rules apply to cars as well). OTOH, the frame could have been bent and, again, the repair bill was too high for the insurer.
Once the insurer writes it off, some riders buy the bike back from the insurer and then try to fix it, use it on the track, or resell it.
If you're not already an accomplished grease monkey with vehicles, I would recommend avoiding salvage bikes or at the very least having an accomplished motorcycle mechanic evaluate all the things that need to be repaired. That will usually cost ~$50 for the assessment.
Dragging knee is for the track, and dragging tail is for the lot. --Kane Friesen
When you're in a car, you're watching a movie; when you're on a bike, you're in the movie. --Robert Pirsig
Identity theft is not Fun