In Marx and Engels's Communist Manifesto, the wage laborer is an individual who works for the capitalist (the owner of a company, firm, or factory). The wage laborer works for subsistence, earning only enough money for housing and food. However, the capitalist employs the wage laborer because the laborer generates capital, or profit. In this way, a wage laborer produces two items when working: first, the wage laborer produces a product for the capitalist to sell, and second, the wage laborer produces capital for the capitalist.
Marx and Engels go on to describe the ways that capitalists are able to exploit wage laborers. For instance, if food, which is produced on an assembly line or in the slaughterhouse by wage laborers, suddenly increases in price, the wage laborer sees no increase in wages. However, the wage laborer still needs to buy food, even though the buying power of the laborer's wages has shrunk. The increase in costs returns to the capitalist as even greater profit. Because they are always engaged in a struggle for subsistence, wage laborers are never able to move above their station in life, always beholden to the capitalist. In this way, wage laborers are not terribly different from slaves (per Deakin and Wilkinson, 2005). Slaves on a plantation traded their labor for housing and sustenance and had little time for personal interest or gain. Just so, the wage laborer is also relegated to a lower class position, constantly working just to survive. The only difference is the sense of freedom—which Marx and Engels argue the wage laborer does not actually have, because the laborer must work for some capitalist to earn the money for subsistence.
Examples of wage laborers are found throughout the world. Marx and Engels provide the example of a worker in a cotton factory producing cotton, but more contemporary examples might be a barista at a coffee shop or a technician working at an automotive assembly line. Hypothetically, the barista works for ten dollars an hour. The wages paid to the barista are made when the barista sells two large coffee drinks. Ignoring the cost of materials, which we might argue are negligible, anything that the barista sells afterward becomes profit for the coffee company. Similarly, the technician makes minimum wage, but the car parts assembled sell for well above minimum wage. In all of these cases, the wages are so meager that the workers must devote all of their time working to keep an apartment. Thus, there is no time for school, no time for personal growth, and no time to get ahead of the position that they already occupy.