Boy Archie - you are opening quite a can of worms with that question.

However, IMHO at one point, somewhere around version 2 or 3 of each product, Netscape was a far superior product. This was in terms of functionality and speed of rendering (remember that an web page is basically text and needs to be rendered to what you see).

Starting in version 4, Microsoft really turned on the juice and made IE a very feature rich, and faster product. Most likely in an effort to bury Netscape (we won't get into the whole antitrust thing). Unfortunately they also made it a very fat client as well. A browser should not be an 25 meg download.

I worked for a broadband cable ISP who switched all their clients from Netscape to IE around that time. It installed very well and delivered HTML/DHTML/ASP content extremely well.

The Mac is another story. It seems that Netscape has quite a following in the Mac world, although IE is also an excellent product for Mac as well.

There are a couple of other choices as well, such as Opera (which is a very thin, very fast browser). But its hard to argue with something that is built into your operating system.