One of the major changes that Microsoft made with the release of the .Net framework was how data was accessed, manipulated, and updated.

A dataset is basically an in-memory database. It can contain tables and relationships.

Each row in a datatable has a rowstate assigned to it. The rowstate is used when you use a data adapter to update the database. Instead of having to call several different methods, you just call da.update. You can also use the rowstate to compare the original field value vs. its current value. I use this when writing audit trail applications and it works very well.