Since heading tags typically make text contained in them larger than normal text on the page, this is a visual cue to users that this text is important and could help them understand something about the type of content underneath the heading text. Multiple heading sizes used in order create a hierarchical structure for your content, making it easier for users to navigate through your document.
In 2007, U.S. advertisers spent US $24.6 billion on search engine marketing. In Q2 2015, Google (73.7%) and the Yahoo/Bing (26.3%) partnership accounted for almost 100% of U.S. search engine spend. As of 2006, SEM was growing much faster than traditional advertising and even other channels of online marketing. Managing search campaigns is either done directly with the SEM vendor or through an SEM tool provider. It may also be self-serve or through an advertising agency. As of October 2016, Google leads the global search engine market with a market share of 89.3%. Bing comes second with a market share of 4.36%, Yahoo comes third with a market share of 3.3%, and Chinese search engine Baidu is fourth globally with a share of about 0.68%.
YouTube is the number one place for creating and sharing video content, and it can also be an incredibly powerful social media marketing tool. Many businesses try to create video content with the aim of having their video “go viral,” but in reality those chances are pretty slim. Instead, focus on creating useful, instructive “how-to” videos. These how-to videos also have the added benefit of ranking on the video search results of Google, so don't under-estimate the power of video content!
Webmasters and content providers began optimizing websites for search engines in the mid-1990s, as the first search engines were cataloging the early Web. Initially, all webmasters only needed to submit the address of a page, or URL, to the various engines which would send a "spider" to "crawl" that page, extract links to other pages from it, and return information found on the page to be indexed. The process involves a search engine spider downloading a page and storing it on the search engine's own server. A second program, known as an indexer, extracts information about the page, such as the words it contains, where they are located, and any weight for specific words, as well as all links the page contains. All of this information is then placed into a scheduler for crawling at a later date.