To be technical, and to borrow a bit. Proletariat[1] are the working class, they work for the Bourgeoisie[2], the people who own the means of productions. That's why I asked why you used demote. Lower, Middle and Upper are strata or ranks within classes. Within the bourgeoisie, you can distinguish:
Petite bourgeoisie: small business owners, shopkeepers
Haute bourgeoisie: industrialists, financiers
Managerial class (in some frameworks): high-paid non owners who control labor
Within the proletariat, you can distinguish:
Lumpenproletariat[3]: unemployed, precarious
Skilled laborers vs unskilled laborers
Labor aristocracy: better-paid, sometimes ideologically closer to capital
Petite bourgeoisie: small business owners, shopkeepers
Haute bourgeoisie: industrialists, financiers
Managerial class (in some frameworks): high-paid non owners who control labor
Within the proletariat, you can distinguish:
Lumpenproletariat[3]: unemployed, precarious
Skilled laborers vs unskilled laborers
Labor aristocracy: better-paid, sometimes ideologically closer to capital
https://en.wikipedia.org/wiki/Proletariat [1]
https://en.wikipedia.org/wiki/Bourgeoisie [2]
https://en.wikipedia.org/wiki/Lumpenproletariat [3]