Bouncy castles, sometimes called bounce houses, are a type of inflatable structure. The term bouncy castle can be used either generically, to cover any type of inflatable play structure or specifically, to designate those inflatable play structures that resemble castles. They are a common feature at events for schools, churches or carnivals.

Basic Design
A bouncy castle is usually a square or rectangular shape, consisting of four main pillars and an opening for children to enter. Some, particularly the larger ones, include slides. A fan, powered by a generator or plugged into an outlet, keeps the bouncy castle inflated, typically by constantly blowing air into the structure. This design allows air to flow into and out of the bouncy castle.

Use
Bouncy castles offer the bouncing pleasure found in a trampoline, but without the hard metal parts. The design achieves this by allowing for air to flow out, which makes the entire surface of the castle yielding. You don't have to worry about the kids getting hurt from deflation because the fan keeps air flowing in. The result is a very bouncy surface.

Availability
Bouncy castles range in size. Small ones hold a couple of children and fit in a room. On the other end of the spectrum are enormous castles that can fit a dozen children and are over 20 feet tall. If you want to purchase for indoor use make sure you've measured the distance to the ceiling to make sure you buy the right size. Bouncy castles are also available to rent for parties. Some companies offer an indoor space with a variety of bouncy castles for children to play if you would like to see them in action.

Safety
Bouncy castles have a weight limit and a limit to the number of kids who can be in them at one time. Too much weight can damage the bouncy castle, while too many children will increase the chance of a collision. Rental companies should have someone onsite to set up and possibly operate the bouncy castle. If they don't operate the bounce castle then you'll want to find out the maximum weight and occupancy so that you can keep the kids safe.