Text box related

Question

Hi,
  I am using a textbox control, inthis textbox i will enter a letter the names starting with that letters should come like dropdown menu as like google search. For example if i type letter 'R' the names like Raghu, Ramya, Raju, Raman,Rama,Radhika etc should come like dropdown. If i type 'M' the names like Manu, Manasa,Meghana,Manya,Mahest etc should come like drop down menu. How to do this these all the names i am fetching from database. please can anybody help me regarding this?