It’s been 21 years since the first banner ad appeared on the web. It ran on a site called HotWired.com, the original website of Wired Magazine, and it asked, “Have you ever clicked your mouse right HERE?” An arrow pointed to an ominous-sounding prediction, which was spelled out in all caps, and read: “YOU WILL.” It was part of a campaign that aimed to visualize the digital future brought to you by AT&T. The vignettes were prescient in just about every instance except for a much-parodied TV spot that asked, “Have you ever sent a fax from the beach? YOU WILL.”