The safest place you can ski is inside the boundaries of the ski area. Most in-boundary avalanche accidents happen when intermediate and expert skiers disregard the closed areas and adventure into unstable zones without proper training.
The Ski Patrol are professionals who take painstaking efforts to keep the inner boundaries of the ski area safe. But, that being said, having a basic understanding of avalanche dangers is suggested. Click anywhere on the below picture and you will be taken to a video outlining the hazards and the ways to protect yourself from an avalanche.