A pizza shovel peel is a tool you use to place pizzas in the oven. This helps prevent you spilling any of the ingredients off the top of your pizza. Some describe this nifty tool as a giant spatula upon which you can build your pizza then place it in the oven.
There is more to it than that, however. A pizza peel also allows you to remove your pizza from the oven as well, without the risk of burning your fingers in the process.