Generally two types: tail dragger or tricycle
tail dragger
require a bit more skill to operate
nose-over and ground loop can be troublesome during take-off and landing
wheels are ahead of the center of gravity which requires careful design so it will not run into problems above
wheels require minimum friction, landing gear place more forward to reduce nose-over
widening gear placement can avoid ground loop
two front wheels support most of the weight
Tricycle
main wheels behind the center of mass
if the main wheels are not back enough the plane will teeter
if the nose wheel sits too high, it can be in flying position before gaining enough speed