Simple Terrain
Simple terrain has exposure to low angle or primarily forested terrain. Some forest openings may involve the runout zones of infrequent avalanches, but there are many options to reduce or eliminate exposure.
Check out the slideshow for examples of simple terrain:
This is low-angle terrain with no exposure to avalanche paths, making it simple terrain.
Nicole Matei 
This skier is in low-angle, simple terrain.
Taylor Clark 
This is simple terrain at treeline.
Nicole Matei Under most conditions you can move confidently through simple terrain. It is still important to watch out for small slopes with terrain traps, openings in forests, and exposure to avalanche paths from above.