I use both. When using ftp:// Firefox SUCK in that.
But also, most of the coding that is used in IE does not work in Firefox. So, you have to learn BOTH.

Yeah, you are saying true! Mozilla Firefox is the best then IE. Mozilla have more important plugins, addon and tools for users. Mostly person using Mozilla Firefox browser.

Internet Explorer is based on the aging, and largely obsolete, Triednt parsing engine. Unfortunately, rather than re-building the engine from scratch, or starting anew with another engine, Microsoft leaves much of the code in the current Triedent, the same as it was half a decade ago.
Another problem is that MS barely lets third-party developers create extensions for IE. While they do exist, they're very unpopular, simply because IE is dying.
Why so? Because Microsoft got lazy. Between the release of (the infamous) IE6, in 2001, and the release of IE7, in 2006, other browsers, like Firefox, Safari, and Opera, gained significant ground in the browser market. Let's take a look at Firefox's release history, between FF1.0, until IE7 came out, October 18, 2006.

• October 26, 2004: Firefox 1.0 final release makes its first appearance.
• November 29, 2005: The 1.5 update is released.
• October 16, 2006: Firefox 2.0 is in final public beta, to be released about a week later.

That's three major builds in less than half the time it took for IE to make a single update. As of late, open-source browsers, specifically, Chrome and Firefox, are on something of a 6-week release schedule. Firefox is already up to version 15 as of this writing, and Chrome (est. 2008), is up to 19, and 21 on the Canary channel. And these browsers all support the latest technologies: HTML5, CSS3, web fonts, you name it. Until IE9 came along, web developers struggled to get any modern design to work properly in Explorer. Heck, it still looks a bit messed up.
As for Firefox, people have gotten drunk off all the extensions: a few people I know can't live without forty extensions giving them various status messages from all their social networks and email accounts. As a result, Firefox has generally gotten much, much slower than, for example Chrome. While Chrome does have extensions, the Chrome Web Store, an integrated software distribution client, puts more emphais on web apps, which don't have to load as the browser launches, but rather are stored locally, or loaded on request.
Does Firefox stand a chance in the future of web browsing? Undoubtebly. Will it beat Internet Explorer, in terms of theoretical attractiveness? It already did, on October 26, 2004. Will it ever be #1? Unlikely. The fact that IE is installed by default on every Windows machine is a major reason why its current user base is so large. Google Chrome also has an advantage in that Google can display Chrome "Chrome Fast" ads all over the net, thanks to Google's AdSense ad client, used by thousands of sites Internet-wide.

I had the same opinion about firefox until today.
Now I see many crashes, when I am trying to load more than 5 tabs.
I am thinking to try Chrome.

I have swaped to Chrome about a year ago, since my old laptop just kept crashing on Firefox.
So far my opinion is that Google Chrome is the most user friendly browser. Really really to use and configure.
And the best part - you can keep it as simple as you like and you can enjoy browsing better than ever

I used Chrome for about 12 months and only use Firefox and IE when I have to test my website. Firefox was great but now it's a bloated browser that keeps on crashing almost as bad as IE.

According to the latest moves,
it is Chrome who is besting Firefox, while IE is keeping its own.

Firefox has fallen to 20% while Chrome has risen to 20% of the market share.
Three months ago it was about (24% fx) by (16% Ch) ratio

Meaning...
Chrome is gaining exclusively from Firefox market share.