The dictatorship of the proletariat, sometimes abbreviated as DotP, is a guiding principle applied in the transition to communism from capitalism. It facilitates economic development to a level at which communism can be implemented, and prevents counter revolution and sabotage from the international and domestic ruling classes.
As the state exists to assert the rule of one class over another, all class society is a dictatorship; the issue that generally drives the class struggle is who is the ruling class. As such, the DotP is not a dictatorship in the liberal, bourgeois sense of the term but a neutral qualifier as to the owner of state power.
Since there is always an oppressor and oppressed in class society (see also social class) due to the contradictions pertaining to the means of production and, more broadly, to the mode of production, it is important for the proletariat to become the oppressing class over the bourgeoisie if communism is to be achieved.
Use of the term by Marx and Engels
According to the Trotskyist writer Hal Draper, Marx and Engels used the term "dictatorship of the proletariat", or words very close to it, in 11 separate works. (In some of those works it appears more than once.)
- The Class Struggles in France (1850), Part I. Marx writes that after the defeat of the June 1848 workers’ uprising, “there appeared the bold slogan of revolutionary struggle: Overthrow of the bourgeoisie! Dictatorship of the working class!”  According to Hal Draper, this is the first use of the term by Marx or Engels.
- The Class Struggles in France (1850), Part III. Marx speaks of revolutionary socialism and communism as involving the "declaration of the permanence of the revolution, the class dictatorship of the proletariat as a necessary intermediate point on the path towards the abolition of class differences in general....."
- Letter to J. Wedemeyer, 5 March 1852. Marx denies that he had discovered classes or class struggle, but said that "what I did that was new was to prove (1) that the existence of classes is only bound up with particular phases in the development of production; (2) that the class struggle necessarily leads to the dictatorship of the proletariat; (3) that this dictatorship itself only constitutes the transition to the abolition of all classes and to a classless society...."
- Critique of the Gotha Programme. (1875), section 4. Marx says that "Between capitalist and communist society lies a period of revolutionary transformation from one to the other. There is a corresponding period of transition in the political sphere and in this period the state can only take the form of a revolutionary dictatorship of the Proletariat".
- Introduction (1891) to the German edition of The Civil War in France. Engels writes: "Look at the Paris Commune. That was the Dictatorship of the Proletariat".
- The State and Revolution (1918), Chapter 5: "The Economic Basis of the Withering Away of the State". Lenin writes: "the dictatorship of the proletariat imposes a series of restrictions on the freedom of the oppressors, the exploiters, the capitalists. We must suppress them in order to free humanity from wage slavery, their resistance must be crushed by force..."
People's Democratic Dictatorship
People's democratic dictatorship (simplified Chinese: 人民民主专政; traditional Chinese: 人民民主專政; pinyin: Rénmín Mínzhǔ Zhuānzhèng) is a phrase incorporated into the Constitution of the People's Republic of China. The concept of people's democratic dictatorship is rooted in the "new" type of democracy promoted by Mao Zedong in Yan'an during the Chinese Civil War.
In a September 1948 report to the Politburo, Mao called for establishing "a people's democratic dictatorship based on an alliance of workers and peasants under proletarian leadership." According to Mao, this alliance "is not limited to workers and peasants, but is a people's democratic dictatorship that allows the participation of bourgeois democrats."
At its founding the PRC took the form of a people's democratic dictatorship. In the Chinese political framework, revolutionary consciousness and revolutionary activity distinguish "the people" from counter-revolutionaries. Within the PRC, the democracy includes united revolutionary classes and supportive political parties operating under the leadership of the CPC. It could include workers, peasants, intellectuals, petty bourgeoisie, and even national bourgeoisie who supported the revolutionary project. 
According to Mao Zedong's "three types of state system", the people's democratic dictatorship is different from both the "Dictatorship of the Bourgeoise" and the "Dictatorship of the Proletariat", but of "the union of various revolutionary classes led by the working class and based on the alliance of workers and peasants". Dictatorship that is a "joint dictatorship of various revolutionary classes". Among them, the working class is the strongest core, exercising leadership through political parties representing its interests. Next came the peasants, the most reliable allies of the proletariat . Then there is the petty bourgeoisie , who are followers at best. Finally, there is the national bourgeoisie , who may desert the people and join the hostile camp of "anti-people". These four classes exercise the "people's democratic dictatorship".
- Hal Draper, 1962. "Marx and the Dictatorship of the Proletariat", section 3. Avail. free at Marxists.org
- Karl Marx, 1850. The Class Struggles in Fance, Part I: "The Defeat of June, 1848", 7th last paragraph. Free online at Marxists.org
- Constitution of the PRC
- Karl, Rebecca E. (2010). Mao Zedong and China in the twentieth-century world : a concise history. Durham [NC]: Duke University Press. pp. 74–75. ISBN 978-0-8223-4780-4. OCLC 503828045.
- Karl, Rebecca E. (2010). Mao Zedong and China in the twentieth-century world : a concise history. Durham [NC]: Duke University Press. pp. 74. ISBN 978-0-8223-4780-4. OCLC 503828045.
- Boer, Roland (2021). Socialism with Chinese characteristics : a guide for foreigners. Singapore: Springer. p. 247. ISBN 978-981-16-1622-8. OCLC 1249470522.