Marxism-Leninism is Marxism as later explained and added to by Lenin, the Russian leader who helped make the 1917 revolution. Marx had written about class struggle and a future without that old ownership. Lenin said you could not wait for that to happen by itself in a country that was still full of poor farm workers, not only factory workers. He argued for a tight, organised party to lead the way, and for a stage he called the “dictatorship of the proletariat” — meaning government held by industrial workers and poor farm workers, in his picture, as part of getting to a revolution that would last. That mix became the official idea-system of the Soviet Union, and later, with more changes, of other communist parties, including in China. People in Taiwan often meet the short form 馬列. Two messy truths are worth saying out loud. First, this is not simply “what Marx wrote”; the Lenin part is doing real work. Second, later leaders added still more names and still more changes, so a textbook that treats Marxism-Leninism as one frozen block is tidier than the history. The hyphen in English is part of the name; it is one idea-system, said as a pair.