What is the working class according to marx?

Marx defined the working class as those who have to sell their labor power in order to survive, typically receiving wages in exchange for their work. They do not own the means of production and are therefore exploited by the capitalist class, who control the economy and profit from the labor of the working class. Marx believed that the working class, or proletariat, had the potential to overthrow the capitalist system and establish a classless society based on common ownership of the means of production.