Answer:
An indentured servant is one whose service is formally contracted by an indenture, or bipartite written deed.
Frequently these were valuable training contracts, for which the father of a young man might have to pay the master a premium, so that his son would be fed, housed and trained in a trade or craft for a period typically of seven years, at the end of which he might qualify to work on his own account.
Alternatively, a man might enter indentured service as a form of bonded labour, in return for a premium, perhaps to pay his debts