MTB in general

There is many different types of Mountain bike some include: Down hill= DH

                                                                                         Cross country = XC

                                                                                         Free Ride

                                                                                         Dirt jumping=DJ

                                                                                         Four Cross=4X
                                                                                         Trials

The three main types i am going to talk about is DH, XC, trials and Free ride.

Definitions and Info
Down hill
In Down hill there is one objective to go as fast as you down a hill or a mountain. they have large study bikes with around 200mm or front and rear suspension. the bike are built for only going down will are very aggressive gears. some only have gear in the back and none in the front, because of this you cant really cycle up hill. To get to the top you have to either have to use a chair lifts or you a dirt bike to pull you up.

 

Free ride
Is very similar to down hill apart from you are generally not racing. The bikes are lighter have less travel/suspension.and it is more for enjoyment then winning or racing...

Trials

This is a kind of off branch of MTBing. it is mostly sett in an urban location.  you have a bike with a small frame similar to a BMX frame. you can have either a fully ridged bike or some Trials bike have front suspension.  this type of cycling came about from Mtbers trying to improve there bike control but has evolved to the stage where there is dedicated bikes and there is even Trials pros.

Funnily enough this is one of the videos that got me into Mtbing 

Cross country

This is kind off like the marathon of MTBing. XC bikes are as lite as possible and people spend thousands of Euro just to shave a few pounds of there bike. People ride XC to  race and just for fun. race tracks are generally a circuit and the racers have to do a number of laps as fast as they can. If the rider is riding for fun this can also be known as trail riding, these bikes are less weight conscious and more sturdy because every gram does not matter if you are not racing.