Have you heard of wage slavery, where people use the term to focus on similarities between slavery and wage like owning and renting a person
I have.  But I do not know a lot about it.  Can you explain?
People generally use it when referring to situations where a person's well being depends on wagers or salary, maybe like someone who lives pay check to pay check
So it is basically when the employees have all of the control and the little guys (employees) are at their mercy
Yes, it has been going on for a long time, there are a lot of the similarities between wage labor and slavery as early as Cicero in Ancient Rome!