Mindfulness of breathing meditation (ānāpānasati) was originally practiced by the historical Buddha Gotama and was used by him as the basis for his own practice, after which, he proceeded to insight meditation (vipassana) through which, he achieved Enlightenment, Nibbāna/Nirvāna. He taught it repeatedly, praising it in many of his Discourses; on how it can bring about deep concentration, calm, serenity, relaxation, bliss, and equilibrium or composure of the mind.
The word mettā in the ancient Pāli language comes from the noun mitta (Skt. mitra) which means friend. Its real meaning is “a friendly disposition”, that is “friendliness”. As a meditation it allows us to eliminate hostile or negative dispositions towards ourselves and others and to develop friendly or positive dispositions. It brings about the escape and mental freedom from negative emotions, such as animosity, hostility, ill-feeling, malice, resentment, bitterness, antipathy, anger, ill-will, fear, sadness, jealousy or stress.