Most jetpacks aren't. The catchy term for personal flying devices includes ducted fans, rockets, engine-powered wing suits, and even hovercraft, but rarely does the device involved actually use jets. Perhaps aware of this incredibly misnamed category, jetpack makers Jetpack Aviation bill their JB-9 device as the "world's only jetpack." Here's what it looks like skirting the Statue of Liberty:

At their site, they describe themselves as Jetpack Purists, noting:

We believe a JetPack should be just that – a jet turbine powered backpack that is capable of vertical takeoff and landing (VTOL), is extremely light and small and can easily be carried around by the pilot. It should be powerful enough to lift the pilot quickly to thousands of feet above the ground but small enough to fit into the trunk of a car.

At their site, they describe themselves as Jetpack Purists, noting:

We believe a JetPack should be just that – a jet turbine powered backpack that is capable of vertical takeoff and landing (VTOL), is extremely light and small and can easily be carried around by the pilot. It should be powerful enough to lift the pilot quickly to thousands of feet above the ground but small enough to fit into the trunk of a car.