Trotskyism is an ideology that emerged from the ideas of Leon Trotsky, a key figure in the Russian Revolution. Though initially part of the Bolshevik movement, Trotsky disagreed with Lenin and the majority of the party on several key issues. Over time, his beliefs developed into a separate, persistent ideology that is often seen as an opponent of Marxism-Leninism.

At its core, Trotskyism is influenced by the ideas of the petty bourgeoisie, a class caught between the working class and the capitalists. Trotskyism tries to present itself as part of the working-class movement, but it compromises with ideas of the ruling class.

Trotskyism is based on the belief in "permanent revolution," which argues that socialism can't be built in just one country, but must spread worldwide. It also rejects Lenin's strategy of building alliances with peasants, instead seeing them as counter-revolutionary.

Trotskyism has caused division and disruption in revolutionary movements. Its theories have failed in practice, unlike Marxism-Leninism, which has successfully led to socialist revolutions. In short, Trotskyism mixes ideas from both sides but remains ineffective in achieving true revolutionary change.