What is Property?

All power structures are rooted in ideology. A shared belief in this ideology is what keeps the structures of power in place. Under capitalism, the edifice of social control is built on the collective illusion of private property, and the sanctity of the so-called “free market.” Any moves taken to challenge this logic will therefore provoke pushback from the system’s indoctrinated cheerleaders, and will certainly catch the attention of the repressive and recuperative functionaries of the state. But as the saying goes… you can’t make an omelette without breaking a few eggs. And you definitely can’t overthrow capitalism without messing with people’s stuff.
So… what is property, anyway? And what do anarchists have against it?