I don't know if you drive a car but you probably know a shopping cart at the local supermarket. That shopping cart has no suspension and you feel every bump on the road in the parking lot. Now, imagine if the same shopping cart had springs to soften the ride. That would be a suspension bike.
Suspension on the seat post, suspension on the front fork for the front wheel, even suspension for the rear wheel, kind of. But mostly front fork and seat post. Softer ride, good for those who don't really care about high performance. The more suspension on a bike, the softer the ride and you will feel more comfortable on longer rides. Its all about comfort. The trade off is performance.
If you drive a car, then you will know that sports cars have a beefed up suspension and its a harder ride but it handles better like on turns. That same sports car may even have low profile tires (little side walls) to make it turn better, more responsive.
Last edited by Garfield Cat; 05-18-12 at 02:16 PM.