Marx and Friedrich Engels's theories about society, economics and politics are collectively understood as Marxism.
Marxism is the culmination of Marx and Engels's great, complete and strict revolutionary theories, formed after they critically studied and extracted the core of German classical philosophy; classic English political economics; French socialism, especially the three utopian socialists doctrines; analyzed the rise of capitalism and the fundamental contradiction movements in capitalist society; and summed up the experience and lessons of workers' movements during the rise of capitalism.