Hash -- not just food

Last week on the phone, while conversing with a computerized voice, I heard, "Please enter your telephone number, followed by hash."
"Hash"??? I looked on the phone dial for some new and different symbol - but found none.
From across the room, Carl rescued me: "It's the pound sign."
OF COURSE.
The British have their own pound, and it has nothing to do with weight. It makes sense that they wouldn't call this symbol, #, the pound sign. Instead, it's HASH.