The Buddha taught many meditation techniques that were already known. In terms of technique what was his contribution ?
What is called yoga today is actually a later development. Patanjali lived about 500 years after the time of the Buddha, and naturally his Yoga Sutra shows the influence of the Buddha's teachings. Of course yogic practices were known in India even before the Buddha, and he himself experimented with them before achieving enlightenment. All these practices, however were limited to sila and samadhi, concentration up to the level of the eighth jhana, the eighth stage of absorption, which is still within the field of sensory experience. The Buddha found the ninth jhana, and that is Vipassana, the development of insight that will take the meditator to the ultimate goal beyond all sensory experience.
[excerpt from Vipassana Meditation]