Originally, no mountain bikes had any rear suspension. So in reality, they were all hardtails. It's a little funny that now that most serious mountain bikers ride on bikes with rear suspension, the term hardtail was created to describe these original bikes without rear suspension, but that is how it goes.
Example : Giant XTC Composite
Also Known As: stiffys, rigid, uncomfortable
Definition: Full suspension simply refers to a mountain bike with both front and rear suspension. Suspension means it has a damper or shock to help smooth out the ride. A mountain bike with no rear suspension is called a hardtail. A mountain bike with no suspension is said to be rigid.
Example : Marin Quad XC
The all mountain category consists mostly of bikes with about 4 to 6 inches (100 to 160 millimeters) of travel. While they are designed to climb hills very efficiently, they are generally heavier and a bit more stout than the typical cross county mountain bike. They can handle a lot rougher terrain as well.
Trail bikes are what most people should be riding. They are an excellent balance between efficiency, comfort, and control. All mountain mountain bikes are light and efficient enough to get you to the top of the hill, have soft enough squish in the suspension to keep you isolated from rough terrain, and have enough travel to suck up the bigger hits that can leave a cross country racer tasting the dirt.
Example : Ellsworth Epiphany
Also Known As: Trailbike
Definition: Cross-country or XC mountain bike riding refers the type of terrain the riding is being done on and what type of ride it is. Most mountain bike trail riding is XC riding. These are rides where you usually pedal along the whole ride without lift access or shuttle and don't need any extraordinary equipment to complete the ride.
Picture : KTM cross country bike (Hardtail)
Picture : Orbea Occam (Softtail xc bike)
Definition: Freeride mountain biking refers to a type of mountain bike riding style. Freeride usually involves large drops, jumps, and manmade stunts. The trails are often accessed by shuttle or ski lift but can be pedaled as well. Freeride bikes usually have large amounts of suspension travel (6" to 8"+) and are built to take a beating.
Picture : Specialized Big hit
Downhill racing records a racers time to complete a course. The shortest time wins.
Downhill bikes are designed specifically for downhill racing. They are built to take a beating, and as efficient as a 40lb. bike can be for fast acceleration. They are all about performance, especially suspension performance, and are not built to really go up hill at all. These bikes are built to get down a downhill course as fast as possible, whatever it takes.
Also Known As: DH
Definition: A 29er is mountain bike with 29 inch wheels. Standard mountain bikes have had 26 inch wheels for as long as it's mattered, but 29ers are starting to make some serious headway.
Not to be confused with a 96er ( 29 inches up front, 26 inches in the rear).
Pronunciation: twenty nine er
Also Known As: Twentyniner, Bigwheel, Twenty Nine Inch Bike
Alternate Spellings: Twentyniner
Common Misspellings: 29er, 29'er, 29"r
Singletrack at Wang Panjang