system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What makes a pizza cutter so much better at cutting pizza than the average knife is? Why don't we use pizza cutters for all foods if they're so much better?
gpt
The crust material is bonded to itself with a decent cohesion, and the cheese/toppings on top is bonded to itself with a decent cohesion, but the bond between the two, between the cheese/toppings and the crust, is a much lesser intensity. If you use a knife to try to separate the crust from the crust and simultaneously the cheese from the cheese (a slice of pizza), you'll likely separate the cheese layer from the crust layer (the cheese will move all over the place).


If you use a pizza cutter, there is a vertical force without the horizontal friction, so a separation of the layers is less likely.


So a pizza cutter is helpful when you have layered foods where the layers can separate, and the distribution as a whole on the height axis is important.


Mhmmm, pizza.