Web Design in a Nutshell, 3rd Edition

Persistence of old browser versions

Speaking of old browser versions, the statistics above show that browsers such as Netscape 4, originally released in 1997, are still hanging around. In fact, statistics show that there are still a handful of hits from Netscape 2.

With the vast volume of web traffic, even less than 1% could amount to millions of users. If your revenue depends on them, you must continue to keep them in mind and make sure that your site is, at the very least, functional on even the oldest browsers.