Originally the game started out its life under the name SubSpace and it was an online only massively multiplayer space shooter. It was a great game but eventually didn't earn enough revenues to stay alive. Not wanting to let it die the game stayed on life support with the help of numerous volunteers. Eventually it morphed into Continuum, an improved version of the base SubSpace client, beefed up and tweaked out. In as far as how Continuum is played, it's simple.
Continuum has a collection of zones which are in effect large playing arenas.
Upon choosing your arena you select from among one of eight different space ships. Each has its own unique strengths and weaknesses so your options are varied. Now it's time to play. When you enter the zone you're weak and easy pickings for stronger players. To charge up you'll need to fly around and collect various power-ups that give you things like stronger weapons, special abilities, and the like.