Bike shoes have stiff soles to distribute the load and pressure points. This reduces hotspots and numbness.
Clipless pedals are pedals without toe clips. They clip into the cleat on the bottom of your bike shoe and release by twisting your heel to the side. Most pedals have adjustable release tensions. Clipless pedals allow you to use more of your leg muscles in the full pedaling cycle instead of just on the down stroke.They also provide more control since your feet don't bounce around on the pedals, instead you can use your pedals to help control your bike. This can come in very handy on bumpy off-road descents.