What is the difference between ground floor and 1st floor?

[M.aadil]

I am always confused about ground floor and 1st floor.
Can someone please tell me whether or not they are same? If not then, what is the difference between them?
Thanks in advance.

 

[Rover_KE]

In British English, the ground floor is at street level and the first floor is the next one up.

In American English, the first floor is at street level and the second floor is the next one up.

Don't ask me why.:roll:

 

[M.aadil]

Don't worry I won't ask you(haha). rules are rules. I know there is a big difference between US & UK english. By the way thanks for your kind reply.