The Content Search Web Part is a SharePoint Server 2013 feature that displays content that was crawled and added to an organization’s search index. It is a very powerful and versatile Web Part, especially when it is used in combination with managed navigation and category pages. The Content Search Web Part allows you to select a result source. This makes it very easy to specify which content should be searched. You can also use Keyword Query Language to add more filters and search terms to the query in this Web Part.