Plugin Actions

I am new to WordPress and looking at writing a plugin that manages user data summaries. I am using the WP_List_Table to list the data in the admin area and i see that you can add actions to each row like edit and delete. It appears to be links to those actions however I don’t know what those links refer to? Are they defined actions using add_actions? I want to edit the data from the list and update the records an i am assuming that would be a new page? Does anyone have any advice on this topic? Thanks so much.