The purpose of the Navigation Acts was to govern the sea trade between the British Empire and its colonies. All of the laws from the Navigation Acts were designed to let England derive maximum profit from her colonies.
The Navigation Acts were comprised of a number of individual laws issued in the 17th century One such law was that all goods carried from one part of the empire to another had to be carried in British ships crewed by at least two-thirds British subjects. Another was that certain products could only be sold in England or within the British Empire such as sugar, indigo, tobacco and ginger. Laws were also passed banning the colonies from shipping hats, iron products or woolen items out of the colony in which they were manufactured. This law was created in order to stop any of the British colonies from developing a robust manufacturing trade.
The Navigation Acts were difficult to enforce because of smuggling. For example, the American coastline had a number of harbors that were out of the way and not plainly visible. Here many ships were unloaded. The Navigation Acts were ultimately unsuccessful in controlling the British colonial trade despite the British government's multiple attempts to enforce it.