Photo Credit: Alex Mead
Seen above is a massive mobile hydraulic crane fitted with a jib. Cranes like this are advantageous because they can be setup and taken down with relative ease, and have large lifting capacities. The jib on this crane allows it to reach far over objects, like the store front in this photo, and access the back of the building far from any open space where a crane can be set up. This allows the workers to position objects, like air conditioning units, on a roof that would otherwise be inaccessible by a crane without a jib attached.