A sentence of transportation could apply for "life" or for a specific period of time. The penal system expected convicts to work, either in institutions or sub-contracted to individual entrepreneurs in penal servitude.
A "transport" who had served part of his "time" might gain a ticket of leave permitting some prescribed freedoms. But exile remained an important component of the punishment. At one time, returning from transportation was a hanging offence.
Transportation punished both major and petty crimes in Britain from the 17th century until well into the 19th century. The British colonies in North America received transported British criminals in the 17th and 18th centuries; Australia served as a standard destination of transportation for a period starting in 1788.