Creating a plugin using ajax

Hi!
I’m creating a plugin that shows on a frontend page a table with data took by the database, actually to insert a row I click on a button that make visible a div with all the fields to insert, I press ok and the page will be reloaded and insert the data on the db, same thing with the editing…

now I wish make this without reloading the page, using ajax

does anybody can help me to show me a simple sample that do this?

thankyou very much