What is a title tag?

What is a title tag and why should you care?
Watch this short clip–>http://www.youtube.com/watch?v=aa64nlJEuNg
When trying to understand social media,posting to blogs,websites, and the like, it also helps to understand a little about the HTML code. Html is and acronym for hyper text markup language, and its vital the success or failure of your site.
Now if your just beginning much of this will be foreign to you, however the more you become familiar with the process or as I like to call it, (all the moving parts) you will understand just how important it is to your system.
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