I believe Townie is a brand name of Electra Bikes. It basically corresponds to the more generic "Comfort Hybrids" category. They are somewhat compact and give you an upright position. Your bike, Pooks, looks like a comfort hybrid to me. They have usually three speeds and often more.
Cruisers are usually lower, longer bikes. Often they only have one speed and coaster brakes, many have three speeds, but seldom do they have more than that. If I'm not mistaken, some motorcycles are also called cruisers, usually those with the very "forward" front wheel.