Auto Complete TextBox Jquery,Json,Asp.net

what is Autocomplete ? A feature that suggests text automatically based on the first few characters that a user types I'm googling for autocomplete using Jquery and Asp.net .finally i got a nice article regarding this but the example is provided in php .Then after sometime i migrated the code into Asp.net with Generic handler and with the help of jquery and json .. This will make a asynchronous call to the server side, with no post back