From my comment a few days ago:

Dialectical Materialism is both Dialectical and Materialist, hence the name. Materialism puts matter as primary, not ideas as distinct from material reality. An Idealist would, for example, say that ideas are generated independently, and it is through ideas that humans shape the world around them. Materialists assert that it is actually material conditions which create ideas, so the ideas of, say, a king are going to be different from those of a serf given their different experiences.

Hegel was an Idealist dialectician. For him, the advancement of humanity was in the “Spirit,” greater or lesser developed societies coincided with differences in development of this grand and universal Spirit. It is through every human acting in their own interests that the Spirit is advanced, people are pulled by their interests and pushed by their passions, and the fulfillment of this Spirit is what drives the course of history. This is dialectical in that contradictions inevitably resolve and sublimate thier premises into new concepts, thesis, antithesis, and synthesis.

Marx was not satisfied with this. Whenever Hegel returned to economics, he became closer to the truth; human history is driven by economic development, not by some grand “Spirit” that humanity is advancing. Marx accepted the Dialectics advanced by Hegel, but on Materialist grounds. This shows, for example, in the theory of Class Struggle, where all forms of production beyond tribal societies have been driven by conflicting classes that each advance their own interests.

The practicality in Dialectical Materialism is that it analyzes concepts in motion, as well as as they appear and disappear. Feudalism could not have lasted forever, as accumulation grew, new classes, the Bourgeoisie and Proletariat, emerged from Feudalism and overtook it. There are no “pure” or “static” systems, everything exists in motion and in context. This is why Marxists say history progresses in spirals, as contradictions play out, there is a quantiative change, so each time this mutually reinforcing antagonistic relationship plays out, it builds up until a large amount of quantitative additions leads to a qualitative change, ie accumulation beget money as Capital, which beget production of Surplus Value, which beget Surplus Value transformed into more Capital, which beget the rise of Capitalism, accelerated by the invention of the Steam Engine, itself a product of all that came before it and laid the foundations for all that came after.

Marxism sees history as a course of endless spirals, it’s a cycle of circles that repeats itself but does so with increasingly changing inputs. As Capitalism continues, disparity rises, the bourgeoisie shrinks in number relative to the proletariat, and the Proletariat becomes further advanced in political thought and more aware of this obscene disparity. This Class Struggle sharpens until it results in Revolution. Marx advanced Socialism not by trying to create a perfect idea in his head and create it in reality like Saint-Simon, Robert Owen, etc, but by learning and mastering the laws of development so that Humanity can apply the laws of Social Science and Political Economy in its own interests just like Humanity does with Biology for Medical use, or Chemistry for materials sciences, or Physics for Engineering.