Meditation (1)

There are generally two different forms of meditation. Yes, I am aware that we could argue, that there are way more than two.. or that there is only one form of ‘real meditation’.. ..but please don’t be a nitpicker here and just try to see, what the riddle really wants to reveal! So.. What are these two general forms of ‘meditation’.. ..and how exactly do they work? (NO mambo-jambo about ‘energy’ and ‘vibrations’ please! Explain in clear words, how our consciousness and our subconscious mind are involved and/or affected.)