Where do downloaded pdf files go on ipad
"It produced overhead transparencies on a black-and-white Macintosh for laser printing. Presenters could now directly control their own overheads and would no longer have to work through the person with the typewriter. In the 2000s, there was a trend of print and e-book sales moving to the Internet,[ citation needed] where readers buy traditional paper books and e-books on websites using e-commerce systems.