Google is currently the industry standard for search engines. Indexing over 4 billion web pages, Google is the largest and therefore the most commonly used search engine on the Internet today.
Its tremendous popularity has brought Google great commercial success. The “AdWords” program allows advertisers to bid on 'pay per click' (PPC) ads that appear alongside relevant search results on the Google website, or on other websites as part of the “AdSense” program used by Web publishers.
Google's PageRank (PR) system has also become a “standard” of sorts for search engine optimizers (SEOs.) Based on a scale of 1-10, PR measures the “importance” of a page based roughly on the number of external sites that link to it. PR is an all-around good tool for optimizing your site for any engine, but particularly if you want to rank high in Google.
Google, while not the first search engine, has become know as the industry leader when it comes to search the web. The founders of Google had a great idea and were the first to implement a search engine with the greatest impact in terms of size, usefulness, and commercializing “searching” the Internet. Google is becoming like Microsoft, you love it or hate it.