SharePoint Hierarchy is one of the important concept that every share point developer must know. I am giving below some explanation about it for enhancement of knowledge The figure given at the left side gives better idea to understand the hierarchy in share point At the top level of the hierarchy is Server Farm. This is physical server which consist of share point installation. It may contain more than one server which we can defined at the time of installation. Next to the server farm is Web Application which is created on server using CA site. This is where all site collations get created and we can have mapping as well as choice of application pool at this level only. In Web Application we can create number of the site collections we can set the top level site and number of subsides below it. Sites or Website is created under the site collection. We can create number of sites in site collection as per the requirements. Sites are the actual place where we have physical interface of all elements like list library etc. List Library are the lowest level element in share point hierarchy. Those are created under only site. It’s very important understand this hierarchy, because We can’t create any element by crossing these.IE. site can only be created under only site collection and not under WA or server Farm.