Ski cross is a type of skiing competition. Despite its being a timed racing event, it is often considered part of freestyle skiing because it incorporates terrain features traditionally found in freestyle. Ski cross courses have both naturally occurring terrain and artificial features including big-air jumps and high-banked turns. What sets ski cross apart from other alpine skiing disciplines is that there’s more than one skier racing down the course. Any intentional contact with other competitors leads to disqualification.
In a time trial or qualification round, every competitor skis down the course, which is built to encompass both naturally occurring terrain and artificial features like jumps, rollers, or banks. After the time trial, the fastest 32 skiers (fastest 16 if not 32 competitors) compete in a knockout series in rounds of four. A group of four skiers start simultaneously and attempt to reach the end of the course. The first two to cross the finish line will advance to the next round. At the end, the big final and small final rounds determine 1st to 4th and 5th to 8th places, respectively.
Boardercross is a snowboard competition in which a four to six snowboarders race down a course. Boardercross courses are typically quite narrow and include cambered turns, various types of jumps, berms, rollers, drops, steep and flat sections designed to challenge the riders' ability to stay in control while maintaining maximum speed. It is not uncommon for racers to collide with each other mid-race.
Boardercross courses share common traits with motorcycle motocross courses, hence the similarity between the names of each sport.
Every boardercross course is a little different. They all slope downhill and are usually quite narrow. Since multiple riders (usually four) compete at a time, the narrowness of the course means getting competitive with your opponents to get and stay in the lead.
Courses include several features- steeps, flats, drops, berms, gap jumps, and so forth. Riders need to stay in control while navigating these obstacles, without losing any speed.