Chili powder (not chile powder) is a condiment that typically contains salt, preservatives and even other ingredients such as cumin. The seasoning can be used in making chile or other soups and stews. Pure chile powder on the other hand is made from ground whole dried chiles with no additives. You can also substitute a pure chile powder in a recipe which calls for "chili powder". An all around good choice is ancho powder. If you want a hot powder try pasilla negro or even hotter, de arbol powder..