Memes

Fine.

Google, define communism:

a political theory derived from Karl Marx, advocating class war and leading to a society in which all property is publicly owned and each person works and is paid according to their abilities and needs.

Britannica:

communism, political and economic doctrine that aims to replace private property and a profit-based economy with public ownership and communal control of at least the major means of production (e.g., mines, mills, and factories) and the natural resources of a society.

dictionary.com:

a theory or system of social organization based on the holding of all property in common, actual ownership being ascribed to the community as a whole or to the state

Merriam-Webster:

a: a system in which goods are owned in common and are available to all as needed

b: a theory advocating elimination of private property

Oxford English Dictionary:

A theory that advocates the abolition of private ownership, all property being vested in the community…

Remember that it is unnecessary to cite sources when dealing with common knowledge.