When designing a website we are, in essence, designing for the browser both in terms of the end-user and the piece of software being used. The most popular modern browsers are Microsoft’s Internet Explorer (IE), Firefox, and Google Chrome, with each garnering roughly a quarter of the market as of May 2012.
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At various times over the past two decades, a single browser enjoyed a significant majority of the market share; at one point, it was Netscape Navigator, and then eventually IE dominated. But with the growth of handheld devices, as well as Google’s entry into the market, Microsoft’s pre-eminence has steadily receded.