One of the most common types of meditations taught in India as part of the tradition of the Indian yogis is mantra meditation. And the most important universal mantra that anybody can use for meditation is the so'ham or haṁsa mantra.
What's significant about this mantra is that you don't need to receive any type of initiation to practice it. It belongs to you, to me, and to all of us. It is a powerful mantra and its meaning, purpose, and benefits are profound.