It’s called “brickmold” because its original purpose was to cover the gap between the window or door frame and the bricks or siding of a house. 

It is commonly made from wood, PVC, or composite materials and is designed to be durable and weather-resistant. The standard width for brick mold trim is 2, 1/4 inches.

Brickmold trim can be used on various styles of houses, but it is especially common on traditional and colonial-style homes. Its classic appearance complements the architectural details of these styles, providing a clean and polished look.