Server controls
The server controls are Hypertext Markup Language (HTML) elements that include a runat=server attribute. They provide automatic state management and server-side events and respond to the user events by executing event handler on the server.
HTML controls
These controls also respond to the user events but the events processing happen on the client machine.
Data controls
Data controls allow to connect to the database, execute command and retrieve data from database.
System components
System components provide access to system-level events that occur on the server.