What are the different types of mountain bike shifters available in the market?

The different types of mountain bike shifters available in the market include trigger shifters, grip shifters, and twist shifters. Trigger shifters are operated by using your thumb or index finger to push or pull a lever. Grip shifters involve twisting a grip on the handlebar to change gears. Twist shifters are similar to grip shifters but are typically located near the handlebar grips.