They move hand over hand from one branch to another while their body is swinging passivly like a pendulum. To be able to do such leaps, it's important to preserve much of the motion deriving from the swinging, which is easier to achieve with long arms. In spite of their skilfulness Gibbons don't escape accidents. It's estimated that about one third of all Gibbons suffer from fractures, which were caused by falls. It enables them to take fruits growing on thin branches far away from the centers of the trees.
Gibbons are very extraordinary primates in any respect.
Famous is one of their ways to communicate. Gibbons do far-reaching singing, which lasts from 20 to 30 minutes. Some Gibbon species, including the Crested gibbon, have throats that are inflated while singing, serving as a soundbox. In most cases both partners or the entire family sings. In addition the singing of the pair is well coordinated and alternating.