Lifehacker has an article Which is Better: Chrome or Firefox? It’s funny because my kid asked a similar question two days ago.
What’s the difference between Firefox and Chrome? And this is more or less what I told him:
The way the Web and browsers work is you can choose any web browser you want. With the Web, you choose what application you want to make web pages with and choose whatever you want to view it, that’s just how it works or supposed to work. Great right?
Next part is the front end and that’s all the features and look and feel that help you browse the web. Some of these features are like tabbed browsing, or bookmarks, a download manager, or add-ons. So if you think the browser backends are more or less equal, you can choose from how the browser looks and what features you might like better.
Finally, these browsers integrate different services. Chrome integrates a lot of Google services and some people like that so they choose Google (if it’s actually a choice and not shoved down their throats some other way). Firefox doesn’t have as many services tied into the browser as Google which can be either good or bad depending on what you like. Firefox is more feel good and more about the Web where Google is more of a Google-centric view of the Web.
For what it’s worth, I worked on Firefox (and shipped 9 years ago tomorrow) but feel free to choose what you want.