excute scalar

Excute Scalar returns type of object. it returns the first column of the first row in the result set.

sqlcommand com= new SqlCommand("select name from tableName where id=15","connection string")

object temp=com.ExecuteScalar();

you get a name of the respective id number 15.

i know it's not enough but so following this link
http://csharp.net-informations.com/data-providers/csharp-sqlcommand-executescalar.htm

Try on Google thousand of link available about the scalar.  

http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlcommand.executescalar(v=vs.110).aspx

It returns the first column of the first row in the result set. If you execute a query to get one specific result (a count for example) you can use this method to get directly at the value.