They make computers, printers and monitors there. They've been doing that for a long time, even before iPads and PCs!
Here is me standing beside a bunch of HP computers from the past. There were several display cases. It was kind of like a computer museum.
They built one in a cool yellow box and named it after a sports car called the Corvette. It must go very fast.
HP even uses computers to help them build other computers. These were in a room that was kept very cool so the machines didn't overheat. Even though there were a lot of computers, we couldn't play games on any of them, so we went to find some other fun things to do.