Technically speaking, a water raft is any floating structure with a flat top. Though it is characterized as a boat, water rafts do not have a proper hull attached to it. It is just because of the buoyant materials that a raft is able to float. Construction wise, raft is so simple that it can be made without even using proper tools.
In the prehistoric time, rafts were made using wooden logs or bundles of reeds tied together. However, the modern rafts are made of drums, pontoons or other inflated materials. Also, unlike other types of boats, which uses hulls or their bottom section to displace water, rafts floats only because of natural buoyancy of the wooden logs or reeds from which they are made.
Depending on the type and application of the raft, they are also provided with superstructure, masts and other necessities for navigation and maneuvering purpose.However, as rafts don’t have any specific hull or hull form, they have the least safety features. Especially in sea, raft has the least protection from the tides. Also because of very less keel, the waves wash over the top of the raft, drenching any passenger or cargo.Moreover, as the propulsion is only through the paddles, rafts tend to drift with the water current, making it difficult to control.

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