I see lots of guys using Opera, others swear to Firefox and yet others say that there is nothing wrong with IE if you've downloaded all the security updates. I'm all confused. If IE is that bad why is it the world standard (it is, isn't it?). Or does it just have to do with the marketing of Microsoft?

Well, back in the day the only competition to ie was netscape and microsoft took the market way by giving the browser away for free - and bundling it with their os.

These days, its a different picture of course. ie remains in the corporate environment for a few different reasons: you don't have to install it, its just there; it runs activex contrrols (which is a bad thing, but some corporate software/deployments have written s/w to take advantage of activex); and joe user doesn't know any better.