There’s four different types of alienation: from the world; from the activity of production; from species-being; and estrangement of man-to-man.
Under the economic system of private ownership, society divides itself into two classes: the property owners and the property-less workers. In this arrangement, the workers not only suffer impoverishment but also experience an estrangement or alienation from the world. This estrangement occurs because the worker relates to the product of his work as an object alien and even hostile to himself. The worker puts his life into the object and his labor is invested in the object, yet because the worker does not own the fruits of his labor, which in capitalism are appropriated from him, he becomes more estranged the more he produces. Everything he makes contributes to a world outside of him to which he does not belong. He shrinks in comparison to this world of objects that he helps create but does not possess. This first type of alienation is the estrangement of the worker from the product of his work.
The second type of alienation is the estrangement of the worker from the activity of production. The work that the worker performs does not belong to the worker but is a means of survival that the worker is forced to perform for someone else. As such, his working activity does not spring spontaneously from within as a natural act of creativity but rather exists outside of him and signifies a loss of his self.
The third form of alienation is the worker’s alienation from “species-being,” or human identity. For human beings, work amounts to a life purpose. The process of acting on and transforming inorganic matter to create things constitutes the core identity of the human being. A person is what he or she does in transforming nature into objects through practical activity. But in the modern system of private ownership and the division of labor, the worker is estranged from this essential source of identity and life purpose for the human species.
The fourth and final form of alienation is the “estrangement of man to man.” Since the worker’s product is owned by someone else, the worker regards this person, the capitalist, as alien and hostile. The worker feels alienated from and antagonistic toward the entire system of private property through which the capitalist appropriates both the objects of production for his own enrichment at the expense of the worker and the worker’s sense of identity and wholeness as a human being. (Source)