In this chapter, we learned the ways to manage data. This was achieved by creating pages, listing it out, inserting the data to the database and retrieving it either to display or to edit, and finally deleting the data. Likewise, we showed you how to list the data at the frontend by making the page. At the end, we created the Order Total Tips module and showed you how it changed the order totals. Using this, you will be able to create modules and pages to manage the data across OpenCart.