In ancient Jewish culture what we currently call an employee was called a slave! It may sound offensive but close observation shows that this is very close to the truth if not a perfect fit. The difference between that culture and the present dispensation designed, largely by the West is that the slave is expected to work for cycles of seven years and have the chance to be free each seventh year. If a Jewish slave remained a slave for more that seven years it was purely because he chose that life.
In contemporary Igbo culture among the traders it is common to find a similar practice. A young teenager works for an experienced trader for six years or so and at the end of the period the master is expected to settle him: give him sufficient capital to start his own business. While staying with his master, his is clothed and fed entirely by his master and paid little of nothing as wages but it only would last a comparatively short time.
In contemporary society we fine slavery still predominant in a modified manner: nice suits, car loans, mortgages, and good wages on a monthly basis. The master expects the servant to work for thirty years or so to earn a significant amount of money called a gratuity (and subsequently pension). For most people that may be the only significant amount after thirty years. The interesting thing is that such slaves also train their children to become slaves for the most part and are very happy when their children enter the Slave Market (I think some people also call it Labour Market).