From the Website:
SOLAR is a fantasy Live-Action Role-Playing game (often referred to as a LARP). Within the constraints of the campaign environment, you create a character concept for a fantasy story and actually play the character. It is much like improvisational theater--you have a framework created by the props and supporting characters and must develop your part as you progress through the storyline. Your character's attitudes, ambitions, and history are yours to define.
The basics of tabletop roleplaying are still prevalent, but SOLAR is primarily a "do-it" game. Instead of imagining yourself fending off a group of orcs with your trusty sword and then rolling some dice to see what happens, you would actually fend off a group of "orcs" (actually players like yourself, who are taking their turn being monsters) with your trusty foam-rubber sword. The results are based upon both your skill and your character's skill with that sword, instead of the luck of a dice roll.
If the adventurous life is your calling, you may play the part of a cunning rogue, a daredevil swashbuckler, or even an honorbound knight. Those proficient in magic are highly useful as well--much fame and fortune can be found for a skilled healer or an elemental adept. Your days can be spent fulfilling contracts, swapping stories in the tavern, or vanquishing the foul creatures that plague these frontier lands. If the epic life is not your style, then you can play the part of a town artisan. You can make your money selling your wares--and information--for the right price.