A floating crane is essentially a vessel that has a crane mounted on it. There are various different types, but all provide lifting capacity on or near the water.
One of the main uses for floating cranes is in offshore construction, for example in the drilling industry. These huge vessels are able to move very large and heavy items and remain stable in most weather conditions.
Floating cranes are also used to retrieve sunken ships. If sea conditions are rough, this kind of project can be very difficult and dangerous. The vessel and its crane need to be stable and the crew needs to be experienced to carry out such a complex operation.

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