There are many types of meditations that can be performed. Different cultures and religious traditions engage in literally hundreds of types of various meditative practices. Different authorities on meditation have their own classification of the core types of meditations. I think all different types of meditations fall into three unique categories.You may want to check out this article for more.
The first class of the meditation is the concentration meditation. This is the most popular meditation. The concentration meditation is the one that fits most closely with the general perception about what meditation should be.
In concentration meditation, you pick an object of concentration. You bring your full attention to this object of concentration. The object of concentration can be anything. It can be a physical object, specific physical sensation or your breath.
You bring your attention to the object of concentration and focus your attention on the object. Within a very short time, you will find that you have wandered away from the object of your attention. This is how your mind operates by default.
The essence of concentration meditation is that when you realize that you have wandered away from the object of your concentration, you bring yourself back to the object of attention. You do this in a nonjudgmental manner.
What is essentially happening is that you are training your brain to improve its concentration faculty. It is like flexing the muscle. You are training your mind to be more attentive and keep up attention for longer periods of time.
The second class of meditation is the awareness or insight meditation. It is also popularly known as mindfulness meditation. In a way mindfulness meditation is very similar to concentration meditation.
In mindfulness meditation you become aware of what you are doing while you are doing it. In awareness meditations your primary aim is to bring awareness to all your activities, feelings and mental states. Just as in concentration meditation you try to improve your attention by focusing on an object for extended periods, in awareness meditation you try to keep up your awareness for an extended time.
In practice you typically start with awareness of your physical self, i.e. your body. Becoming aware of your body may sound like nonsensical as you may think you are already aware of your physical body.
But that is really not the case. Because we are usually very busy with thinking, planning, ruminating and doing things. We usually just don’t pay attention to our body unless it becomes sick.
Mindfulness meditation is essentially awareness training. By default we are aware of what we are doing only for a very limited set of activities. With mindfulness meditation we train our awareness to be present for more of the time.
After having practiced the awareness of the physical body, one goes on to become aware of one’s thoughts. You try to become aware of the kind of thoughts your mind is engaged in. Whether those thoughts are about something that happened in the past, or it is in anticipation of what is going to happen in future.
Further on you can practice becoming aware of your feelings or emotions. This is recognizing what is your state of mind. Whether you are feeling happy, sad, angry or neutral at the current moment. You practice trying to keep up the awareness of your current emotions as moments pass by.
The third and last type of meditation is visualization meditation. Again there are many forms of visualization meditations that people practice. The main idea is to repetitively practice a particular type of visualization.
Some of the examples of visualizations involve imagining yourself getting cured of a disease, getting showered with positive energy or getting purged of negative energy. One of the popular type of visualization meditation is called loving kindness meditation. You imagine sending loving kindness to your loved ones. You gradually expand the circle of people that you send loving kindness, the circle can potentially involve people you find difficult to get along.
The visualization meditation is a form of conditioning training for your mind. By repeatedly visualizing something you condition your mind to be comfortable with that thought or idea. It may help form certain habits also.
In summary there are three high level categories of meditations: the concentration meditation, awareness or insight meditation and the visualization meditation. The concentration meditation improves attention. The insight meditation prolongs the awareness. The visualization meditation can help with forming habits or behavior conditioning.