The title tells users and search engines what the site or page is about. Make sure titles are clear about what users should see on the site or page. This is one of the most important steps, as the title is directly what shows up in search results on search engines. Also make sure not to repeat keywords in titles, as this can be seen as trying to spoof results. A good page title should be no longer than 70 characters.
The description is what shows below the site's or page's title on search engines, though some search engines, such as Google, will not always use the set description. Depending on what the visitor is searching for, the search engine may provide a different description. A good description is between 130 and 160 characters and tells an accurate description of what the site is about. Here is an example description for a mobile website builder: The fastest, easiest way to build a great looking mobile website in minutes. Includes hosting, site analytics, click-to-call, mobile maps and more