Search Engine Optimization completely depends on the search engine. So let's first understand what search engines are?
What are Search Engines ?
Search engines are software's designed to search the information on the World Wide Web. Search engines have two major functions - Crawling and Indexing.
Google, Yahoo, Bing, Baidu, Ask, AOL.com, WOW, WebCrawler, MyWebSearch, Infospace, Dogpile, DuckDuckGo, Blekko and Contenko are name of some search engines.
Google is the top search engine and is used by 70% - 80% people around the world. Rest 30% - 20% use the other search engines mentioned.