Secret admirer

Some secret admirer sent me a number of questions that I responded to a few seconds ago, so I thought I'd post them here as well. I didnt want to type all the answers, so I googled most of them instead.Here is my answer and his queries:

Please see my replies inline.

vivek goyal wrote:
please give me answer of some question

what's dif b/w html server control & web server control?

http://www.w3schools.com/aspnet/aspnet_controls.asp

what is view state?

http://msdn.microsoft.com/msdnmag/issues/03/02/CuttingEdge/

what is postback?

Control data is sent from the client to the server.

what's diff b/w data grid & data list?

In short, a datalist control is a lightweight datagrid control.

what is index & diff b/w clustered & non clustered index

An index is used to speed up database queries. When a table (for example) is indexed on a certain column, the database server maintains special data structures that can allow quick searching on items in that column. Also visit http://www.sql-server-performance.com/gv_index_data_structures.asp for information on clustered vs non-clustered indices.

can data set work in connected environment?

If you need connected "recordset" functionality, consider DataReader instead.