After the release of Windows XP in 2001 and for a few years that followed, Internet Explorer 6 was the biggest, most important browser in the world. And for longer, it has been the buggy browser that's overstayed its welcome. Microsoft announced it would support IE6 through April of this year back in 2009, and today (along with XP and Office 2003) is the last day Microsoft will provide updates. Unless you're an old user who couldn't care less or are somehow nostalgic for a broken web, it's finally time to say goodbye.
Internet Explorer 6 is, by now, a bad joke
IE6 is almost universally reviled, and for good reason. Microsoft got cocky in the mid-aughts after beating down Netscape Navigator; because Internet Explorer overall held more than 90 percent of the market, it took a solid five years before IE7 debuted. Meanwhile, security issues slipped through massive cracks, with fixes coming in few and far between. (Nevermind the fact that IE6 was never fully standards compliant.) It got so bad that full-blown campaigns were launched calling for its death. User antipathy contributed directly to browsers like Firefox and Chrome being able to wrest users away from IE in general, and you can generally see a distrust for Microsoft's actually good browsers to this day. Even Redmond got in on the joke.
Unfortunately, the 12-year-old browser still commands 4.15 percent of the market, so it's not completely gone. So do your loved ones a favor and upgrade them to literally anything else. They'll thank you for it.