What Internet browser do you use and why?

It's very much a personal thing, depends on what features you must have, the 2 main rivals to IE each have their own unique features.

So you're question is really unanswerable - there is no absolute "best". But if you're asking which browser each person thinks is the best, for me its Chrome.
 
I don't think it was a "which is best" question. Just which one do you use.

Personally, I use FireFox, but recent changes may have me looking elsewhere. Not everyone wants to be connected everywhere, all the time.

-Wolf sends
 
For PC i'm using the latest Firefox Dev Edition, it supports multi-threading and consume smaller amount of memory then Chrome do.

For Android: on my 4 years old HTC Sensation i'm using Dolphin browser with Dolphin Jetpack. Find it the fastest browser for slow devices and it also has Extensions with Adblock support and Flash support. Next is Firefox, also because of extensions, but it's not for the slow devices.