What is an ultrabook?

Can anyone tell me what an ultrabook is and what is the difference between a normal laptop?

Ultrabook is a registered trademark of Intel for particularly thin and light notebooks with Intel processors. In order to be allowed to bear the name, the devices must meet a number of requirements. These include a long battery life, acceptable performance and tablet computer-like properties such as quick waking up from standby.

https://de.wikipedia.org/.../Ultrabook

So they are just a certain type of laptop.