There are many types of meditation techniques. More commonly taught includes :
(a) Third Eye Meditation : the attention is constantly redirected to the spot between the eye brows. As a means to silence the mind.
(b) Chakra Meditation : Focus on one of the seven chakras of the body, using some visualization technique and chanting a specific mantra for each chakra (lam, vam, ram, yam, ham, om).
(c) Trataka Meditation : fixing the gaze on an external object, typically a candle, image or a symbols (yantras). It is done with the eyes open, then with the eyes closed. To train both the concentration and visualization powers of the mind.
(d) Sound meditation (Nada Yoga) : Start with meditation on “external sounds” such as calming ambient music. As time goes by, the practice evolves to hearing the ‘internal sounds” of the body and mind. The ultimate goal is to hear the “ultimate sound” (para nada), which is a sound without vibration, and that manifests as “Om”.