Refresh client browser when adding a new row to a specific table

My scenario:

After the client logs in, my user will be redirected to the index.aspx page. Inside this page I will put one div with a gridview inside. This gridview will display data from a single table.

My question is: how to update this gridview always that one record is saved in this table?

P .: I have seen many examples using the push-push technique, comet, ajax, etc. I don’t know how to do this, and I can’t find a really simple example.