Two browsers may not be enough. Despite the fact that there are industry standards for browsers, as ratified and promoted by the World Wide Web Consortium, there are wide variations in the adherence to the standards, there are some gaping holes in the standards, and some web sites and web site development tools play fast and loose with the standards.
I have four browsers installed, three of which I use with some regularity: Internet Explorer, Firefox and Chrome. The fourth is Opera, but I don't use it much. IE is essentially the browser I use to update my Windows XP computer, and not much else. I switch back and forth between Firefox and Chrome most of the time.
A long time ago, Microsoft made the browser world more of a mess by adding its own version of Java to IE. However, they corrupted Java to favor their own software development tools (This IS the Microsoft way of doing things), and Sun, owner of Java at the time, successfully sued to have Microsoft remove Java from IE. So now, we all have to download and install the latest Java, as well as Flash Player and Acrobat Reader to allow all our browsers to work even halfway reasonably. Lots of web sites use Java and Flash, and Acrobat PDF documents are ubiquitous.
The place where the WWWC browser standards come up really short is printing web pages. Part of the problem is also that many web site developers do little to test how their web pages look when printed. Yet every day, people have to print web pages. I routinely do a print preview of most any web page before printing it, and even then, what I see in preview is sometimes not what I get. I also use Firefox more for printing web pages, because you can do a print preview and then change the scale of the web page if you do not like the way it looks. As an example of this, I print web pages for the items I sell on eBay. To do so, I have to change the print preview scale setting from "Shrink to Fit" (the default) to a scale of 50%. Then the printed pages are completely readable instead of bleeding off the page to the right. Is this a browser problem or an eBay screwup? I dunno. I have a workaround that meets my needs. I also use browser print preview to print only the pages I can use, because sometimes the browser print function inserts blank pages and because I have no need for the advertising at the bottom of the web page.