HeSPU vs HSPU

I don't understand the difference between HeSPU and HSPU.

HSPU is on parallets but HeSPU is on the floor? But essentially the same exercise? :?

I can easily perform HeSPUs (I think) until my nose reaches the floor.

I prefer nose to my head touching the floor, because I can look at the floor and would have thought that this is more comfortable for anyone, since it's the regular HS position.

Negatives is when you are using your whole body strength (HS position), correct?

A headstand pushup has a more limited range of motion. It is when you only lower down until your head is touching the floor.

As opposed to a handstand push up where your head goes down even farther

Handstand push ups are far more difficult.

A negative is any movement where you are slowly lowering something, like your body in the first part of a push up or your legs in a hanging leg lift. The point is to do them slow.