VS 2010 Datatable and connection

Hello everyone,

I havent got an access database or MySQL databse either. Soo with that in mind, how to I use a datatable so I can store usernames and passwords etc for when users log in? and to also, create new ones, update current ones and delete them when using the program with buttons and textboxes etc ?

Ive tried youtube and various of places but they dont have what im looking for. Just simply want a table to store usernames and passwords so when they come to log into the program it compares what theyve entered to whats on the table.

Thanks

:)