Lighting fixtures are the physical components that hold and support a light source, such as a bulb or LED. They can range from simple and basic, such as a bare bulb socket, to more elaborate and decorative, such as a chandelier or wall sconce. Lighting fixtures serve to protect the light source, direct the light where it is needed, and provide a means of physically mounting the light source.

Lighting trim, on the other hand, refers to the decorative or functional parts of a lighting fixture that surround the light source. This can include rings, reflectors, lens covers, and other components that are designed to enhance the appearance of the fixture and/or improve the performance of the light. For example, a trim ring can be used to cover the rough edges of a cutout in a ceiling or wall, while a reflector can be used to direct light more effectively or minimize glare.