I have practised & taught meditation for 40 years. I was talking recently with a friend who has done the same, but with different yoga systems (from the ones that I had been involved with), for maybe 35 years, & I was asking her how her classes are coming along. She replied that there are some people who turn up with very definite ideas of what meditation is, & how to do it. "I was like that, once", I replied.
Meditation is called dhyana in sanskrit, sanskrit being the language of yoga. It is the 7th step of ashtanga yoga, the yoga of 8 limbs. The limbs being steps, starting with yamas which are like speciifically recommended vows that we make to ourselves to be a worthy person, & this is for our inner being. For the outer being, & of course they also greatly affect the inner being, we have suggested niyamas, which are beneficial rules of conduct. Yamas & niyamas together, are considered to be the first stage of the ashtanga yoga system of a great sage Patanjali. It is this ashtanga yoga that I am referring to here. Patanjali revealed, in a series of sutras, exactly what happens in the inner spiritual journey, & the steps that systematically unfold.
Next limb is asana, postures, which in this system also means being able to sit in a steady pose for meditation. Followed by pranayama, specific yoga breathing practices which not only provide the fuel for our spiritual journey, but also "set the stage" for the spontaneous happening of the next step: pratyahara, sensory withdrawal, a state of being whereby we are simply completely in the inner realms, & we are not affected by any of our senses, it is as though they have stopped, suspended in time, & this also includes body awareness. Dharana, concentration, follows, & in the yoga systems, many different concentration techniques are taught to actually bring about the state of dharana. Preceding that are also techniques to create the state of pratyahara.
Meditation, dhyana, is a state of being, & is the next stage on from dharana. It is a natural flow-on. The more we consistently have a dharana practice, the more we naturally move into the inner state of meditation, &, as time goes on, the more we are living in this same meditative state in our lives. It is a profound state.
Some of us have learnt specific meditations, usually from a guru based yoga system. This can tend to create the situation whereby we believe that the system that we have learnt, is the only way. It is not. There are many ways, many yoga paths, many meditation techniques to get us there. Not all are yoga. Meditation does not belong to yoga. Some meditation techniques are incredibly simple. The thing is, simple is often the easiest, & therefore the option that we are most likely to keep doing.
What I did find on my meditation journey, is that it is very easy to spontaneously slip into meditation in your yoga practice, & in time, just by being present in the moment. My very 1st yoga teacher had us all practising meditation in our 1st class. He didn't say what it was, he just gently led us into it. My next yoga teacher taught me mantra - specific sounds, yantra - geometric symbols, mandalas- circular meditative designs, & tratak - candle gazing. I was so glad that I had this background before I became involved with a guru-based yoga system, because I already knew that there were many ways to meditate. In fact, when I finally relinquished my personal guru-meditation, & all the dogma around it, I can truthfully say that my spiritual life soared.