Thirty years ago, on July 25, 1996, AT&T announced a promotion and distribution deal with Microsoft that made Internet Explorer 3 the default browser for its WorldNet internet service. AT&T was launching WorldNet to challenge CompuServe and America Online, and it needed a browser. Netscape Navigator dominated the market, but Microsoft was desperate to catch up — and owned the operating system.

Under the arrangement, WorldNet software shipped pre-loaded in versions of Windows 95 delivered to PC manufacturers, with IE 3 as the default browser. Netscape Navigator remained available, but only as an option. Tom Evslin, then AT&T's VP for WorldNet, told The Register decades later that the decision came down to money: AT&T paid per activated copy, and he believes Microsoft essentially gave its browser away — though he admits he is not entirely sure after all these years.

The strategy worked. By January 1997, Microsoft claimed IE's corporate usage had more than tripled since August while Netscape's share fell. WorldNet itself briefly became the world's largest ISP by one contemporary measure before expiring in 2010. Internet Explorer went on to dominate the browser market for over a decade, and Microsoft's bundling tactics eventually triggered antitrust action on both sides of the Atlantic — including the EU's browser choice screen in 2010. The deal stands as an early lesson in the commercial value of being the default.