As sucessfull blogger you should always want for your users to stick around on your blog as long as possible, you can give your users good idea on what should they read next with realted post widget. If your users is reading some post on your blog that they find interesting this widget will automaticlly scan your blog for similar posts and display it wherever you want on your blog.You don't need to register to be able to use this widget or edit any kind of code.
This widget is provided to you by LinkWithin, here is picture example of how the widget looks like:
If you would like to found out more about this widget or put this on your blog visit LinkWithin.