Here are some corrections, since you have a wrong idea.
1. There are standards, one constant. It is the W3 Consortium and everyone follows their standards and recommendations. Well, everyone but Microsoft and their IE. There's no browser that fully supports all the standards but most of the current ones at least follow them, if they do not support some of the advanced features. IE is a subtle exception there.
2. FF is not a new browser, it is simply stripped down Mozilla, which is the open source engine for NN ever since version 6. Reading up on the history won't hurt but in a nutshell: NN4 was old and could not compete with IE4, MS released IE5 and shattered NN5, which was consequently never released, Netscape only worked on fixing version 4. Some Netscape programers fled and created Mozilla, a light (around 120k program file initially), fast, standards-compliant browser. Mozilla grew and became a giant suite and guys decided to offer a stripped down version called FireFox. Netscape7, Mozilla and FF all share the same rendering engine.
3. Once again, most of todays browsers (Mozilla, FF, NN7, Opera7, Safari, Konqueror) follow W3 standards, which are widely accepted as web standards. IE follows MS standards first and then W3 standards. With a correct doctype, IE gets a little closer to the rest of the browsers, just enough to provide support for simple css driven websites.