The popular choice for general off road riding, and versatile enough to go on roads, carry luggage, (usually), and just about go anywhere, hardtail mountain bikes have a rigid double triangle frame and a suspension fork to take some of the sting out of off roading, and to give better control.
As they go up in price, they get lighter, the equipment gets smoother and works better and there is more adjustability in the forks in terms of damping and rebound
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