I don't remember when it happened, exactly, but the expression "to search the Internet" morphed into "Google" at some point in the not-too-distant past. And I use it myself: when I want to search for information, I almost always hunker it into the Google search engine. Thanks to modern Internet browsers, I don't need to visit the Google homepage all that often as I can simply type in what I want to search for and the browser does the rest for me. My default browser is Google Chrome for the simple reason that it simply and easily synchronizes my bookmarks between all of my devices, although I understand that Chrome is not the only browser out there with this facility. One competitor browser is Firefox.
Now, last November, Firefox signed a deal with Yahoo! to change the default search engine; that's right, unless you change it, if you install Yahoo! and tap into the address bar your search term, it'll hit up the results using Yahoo! rather than Google. And we have also seen Yahoo!'s search share tick up at the expense of Google, by 1.6%. Google still have almost two thirds of the default search engine market, but have gone on the offensive by chasing Firefox users to ask them to switch to Google rather than Yahoo as a home page and a search engine. There's a message that appears at the top of the screen when navigating to the Google page that says, "Get to Google faster. Make Google your default search engine" along with "Sure" and "No thanks" options. This joins the message that says, "Come here often? Make Google your homepage," and responses of "Sure" and "No thanks" options. I've seen these messages on Internet Explorer, which I am condemned to use at my office, where Google Chrome is not allowed. And yesterday, Google used Twitter to encourage Firefox users to switch back with a link to a new page for Firefox users to help them back entitled "This one's for all the Google Search-loving Firefox fans out there."
This sort of search engine battle has been fought by all of the major search engines over the years and it results in a few percentage point swings in either direction. It seems that the search engines are happy to tussle over that loose few percent, but many users have their own favorite search engine and will switch to this no matter what browser they use. The search engine user pool is important to these companies because it determines the potential advertisement revenue that may be generated... but with such a large share of the search engine, Google are not going to lose their dominance overnight. Yahoo! have much to gain, having under 12% of the market at this time.