Yes and no. A black hole is defined as the volume behind the event horizon, the "point of no return".
The event horizon is not a physical surface, you only have its definition: you wouldn't know it's a point of no return unless you waited for an infinite amount of time. A good approximation of the event horizon is the surface where the escape velocity is the speed of light.

Nevertheless, black holes are real objects. Their gravity has effects on the outside world. They are created by a stellar collapse. They can orbit around another massive astronomical object.