Ancho is the name for a dried poblano pepper. Their average size is 2 inches wide by 4 inches long with a pointed tip. They have a wrinkled skin which is dark burgundy to almost black in color. Anchos yield a large amount of pulp relative to other chiles.
Chile de Arbol
Chiles de Arbol are small orange-red chiles 2 to 3 inches in length with a 1/2 inch width. These peppers are very hot.
Chipotle
Chipotle are jalepeñoes which are dried over a warm smoke. The dried chiles are 2 1/2 inches by 1 inch and have a dark brown color. The are usually purchased canned in a tomato sauce called adobado. The sauce is an excellent seasoning for beans or any other dish where a smoky spiciness is desired.
Guajillo
Guajillos vary in size but an average one is 4 1/2 by 2 inches with a blunt end. Their brittle and translucent skin is bright red. They have a thick, brittle skin and yield relatively little pulp.
Mulato
A Mulato looks much like an Ancho but looks darker when held up to a light. They give a dish a medium-hot, non-sweet taste.
Pasilla
Pasillas are a long narrow chile measuring about 5 by 1 inches. They have wrinkled skin and are very dark, almost black. Pasillas give a dish a hot and very complex flavor.