Pâte brisée is ‘broken pastry’ in that the flour and very cold fat (butter and/or lard) are cut into each other before adding water, creating pockets of air formed when baking. The trick is to not overwork it but if you give up you can buy it ready made in the refrigerated section of a French supermarket (the cheap ones aen’t always very good).
Variations on pâte brisée include
pâte à foncer: with the addition of an egg yolk and some sugar, to make a firmer crust
pâte sablée
pâte sucrée: this is similar to sablée but with less butter, whole eggs and powdered sugar. It’s often used for a flan pâtissier.
Image by Romain Behar