English and dutch merchants created a well-organized system for "redemptioners." what was this system for?

During the 18th and early 19th century English and Dutch merchants created a well-organized system for "redemptioners." This system consisted of poor European immigrants that travelled to America and, in order to pay back for the voyage, they had to sell themselves and sign an indentured servitude contract for a specific period. During this time, usually 5 years, redemptioners had to work as farmers or servants. Once the contract ended, the redemptioner was free to work in other place.