Microsoft Internet Explorer
Microsoft Internet Explorer, or MSIE, is currently (2007) the most popular web browser due largely to its inclusion in the Microsoft Windows operating system. Because of this, and despite its many bugs, it is also the browser which is the most widely supported by web sites.
There are apparently a number of web sites dedicated solely to documenting bugs in MSIE, and ways to get around them.
Version 7, the latest, is widely regarded as being a significant improvement over earlier versions, both because of the long-delayed inclusion of tabbed browsing (a feature supported by Firefox/Mozilla for many years prior to MSIE7's release) and for having fewer bugs.
MSIE6 and earlier do not properly display "display:none" CSS elements in between normal ("display:block") elements. A workaround is to use "position:absolute" and "visibility:hidden" instead, with appropriate left, top, and width attributes to prevent scrollbars for invisible elements.