Title tag optimization is important because the content of the title tag is used by:

• Web browsers: To label the web browser’s tab(s) (Older browsers used to display the title of the web page in the browser’s window title)
• Search engines: As the clickable headline for listings on Search Engine Result Pages (SERPs)
• Search engines: To determine the topic of the web page. Search Engine spiders or crawlers analyze the content of the page title and then translate the page topic.
• Social bookmarking sites and Web browsers: To assign a default value to bookmarked web sites
• Users: to --Identify the web sites that are likely to contain the information they are searching for within the list of web sites on a SERP --Locate the tab in their web browser which contains the site they want to view --Find the web site they have bookmarked in their browser --Determine whether a web site that others have bookmarked in a social bookmarking web site is worth checking out