A lifting body is a particular shape of reentry vehicle; for example the Orbiter of the Space Shuttle has a lifting body shape.

During reentry, a reentry vehicle has an enormous amount of energy- in most cases enough to melt the whole vehicle several times over(!)

Luckily a blunt body reentering ends up putting most of its energy into the air, and (comparatively) little goes into the vehicle.

The lifting body approach is to generate enough lift to reduce the rate that the speed is lost, and minimise the temperature that is reached; and minimise the g force on the occupants. This works, but one downside is that the heating is far longer, and more heat energy leaks into the vehicle.