In the next stage, switch back to the Source view. Here, you will see the code or markup generated for that item:
Figure 2.2.6: The code or markup generated for an item is selected here
Keep in mind that this is specific to Microsoft, but you can still recognize it. You basically have an ID and Label1 attribute, which is an attribute. This is how you refer to the item in your C# code. You can change it to something more meaningful, say sampLabel, for sample label.
Here, runat="server" means that the content that the label displays can be generated automatically and dynamically, for example, over the course of your connection to a web page or server.
The Text control is what you see. Thus, if you remove the word Label and then switch back to the Design view, it will just say sampLabel, which is the ID:
<asp:Label ID="sampLabel"...