Stephen Hawking's Universe EP5: Black Holes & Beyond (5/ 5)

Are black holes infinitely small "holes" with a large magnetic field that make them appear large or are they giant black spherical stars?

They are like a black spherical stars. In the center is the infinitely small region known as a gravitational singularity.
I have trouble myself understanding singularities but I'm working on it.
Imagine the tip of hair with a mass of the entire universe. A BH's shape is something weird than that. In fact, one cannt imagine that point, which is called singularity, where all the laws of physics fail. But what defines the 'shape' of BH is the event horizon, beyond which the BH starts to grab things, even the light and magnetic field. In other words the starting point of gravitational influence.