Recreational frames are 4 wheel, made from nylon or aluminum, and some are carbon-reinforced. Truly aggressive skaters are into rail sliding, stair riding, stair bashing, curb grinding, wall stalls, catching major air, 180's, 360's, and backwards cross-overs. These skaters are likely male, between the ages of 10 and 20 years, and they roll skates over quicker than any other type of skater. And they also occasionally roll them over anything or anyone who gets in the way. These skates can be either hard shell or soft shell, but either will be more durable than most other skates.
Shells are a little higher than race, for more stability and support.
Aggressive skates have a very durable nylon frame, and 4 wheels. Most hockey skates look like ice skates. They are usually laced skates and have 4 wheels. The boot is usually either leather or ballistic nylon or a combination of both. Heights of hockey skate boots may vary.