Pie plate vs pie dish
A pie plate is a shallow pan with sloped sides used for pies with a pastry base, while a pie dish is a deeper vessel, often with a rim, used for pies covered with a pastry lid only.
The distinction tracks two traditions. The American pie plate, usually about 23 cm across and 3 to 4 cm deep, holds a bottom crust and often a top one; the British pie dish is deeper, frequently oval, and its flat rim exists to anchor a pastry lid over a filling with no base.
Material matters as much as shape. Metal conducts heat fastest and gives the crispest bottom crust, glass lets you check the base for colour, and ceramic looks good at the table but bakes the base slowest, so consider a spell on a preheated baking sheet.