Dialectical materialism is a way of understanding reality; whether thoughts, emotions, or the material world. It is a scientific methodology developed from the principles of dialectics and materialism, and is the theoretical foundation of Marxism.
Although it was developed by Marx and Engels, the term dialectical materialism was never actually used by either, but appropriately summarizes their philosophical outlook.
Vulgar Materialism
Contrast to dialectical materialism which holds that material and the ideal have a dialectical relationship, vulgar materialism holds that only the material is important and ideas have no power to change this material reality.