What is the difference between GANG and WAY in switches?

3 Gang switch has 3 individual switches lined up side by side. 2 Gang switch has 2 individual switches lined up side by side. 1 Gang switch has 1 switch.

2 Way is a switch that controls a light where there is another switch that also controls the same light, such as at the top and bottom of the stairs. 1 Way is that it’s the only switch to control a light.