If you're in the market for a new boat, you probably need to choose between an inboard engine and outboard motor; the inboard engine is built into the boat compartment, under the flooring. Like a car engine, an inboard engine is a permanent part of the boat and not meant to be removed. The outboard motor is portable and attached to the back of the boat with heavy-duty clips. While each may have their advantages, note when you want to opt for the inboard engine versus the outboard motor.
Water sports
If you're getting a boat for water sports of any kind, you want an inboard engine. Because these engines are built under the boat, their propellers are lower in the water; this means more room between those propellers and swimmers getting in and out of the boat. An inboard engine also allows you to have a step or platform behind the boat, making it easier to get into and out of the water.
The placement of the inboard engine may make it easier to control swells--the waves created when your boat cuts through the water. A propeller that is closer to the surface of the water, such as with an outboard motor, will create higher swells that tend to be near the center of the boat, getting in the way of skiers. An inboard engine's propeller is lower in the water so the swells spread out, away from the boat. This creates a smoother surface behind the boat for water sports.
Entertaining
If you plan on doing any entertaining on your boat, you want an inboard engine; the sound of the engine is muffled better since it's built and placed under the body of the boat. This can also give you a larger floor space for more guests on your boat.
Convenience and safety
An outboard motor is somewhat easy for someone to steal; if you keep your boat on a dock and not in a locked storage facility, you would need to remove the motor and lock it away at the end of every day on the water. Along with added security, an inboard engine will also have its major components placed so that they're easily accessible from under the boat's floor; with an outboard motor, you may need to remove the motor from the boat and set it on the dock in order to make minor repairs. This makes an inboard motor more convenient to maintain and repair and a safer option overall.