Much like any other organised philosophy or religion, the Buddha Dharma can be divided into subgroups. And here we can name and discuss the three major schools of thought. Of the three ways or vehicles, the most well known and practised are Theravada the small way and the Mahayana the great and/or middle way. The lesser known way of Vajrayana or diamond or thunderbolt vehicle is sometimes mentioned as a part of the Mahayana but is different enough that many of its practitioners feel it is a way of its own. It is said that the Buddha gave 84000 teachings during his over 40 years of teaching. That would be way too many for any one individual to follow all in good conscience. So it is best if one approaches this vast array of teachings like a pharmacy. One takes only what one needs at the time as it would not be advisable to take everything at once. In this way, we can see the three ways not as being better or superior to one another but as being different ways for different people.
The Theravada school is likely the most conservative of the three and had a very high proportion of monks and nuns. It started mainly in Sri Lanka and spread into South-East Asia. The major tenants of Theravada Buddhism avoidance of negative behaviour and doing no harm are central to its teachings. Its foundation consists the understanding of the eightfold path, Karma, impermanence, or precious human existence, and the cycle of suffering. Refuge in the three jewels of the Buddha, Dharma, and Sangha is taken as one begins the path to liberation. It is worth mentioning two things here, that liberation or the small enlightenment and enlightenment or Nirvana are not necessarily the same thing. Secondly one can say that the Theravada path to enlightenment may take aeons of aeons.
Mahayana Buddhism spread mostly to the west of India to Afganistan and through to Mongolia and into Japan, there is also some evidence of it as far south as Indonesia. The Mahayana school maintains all of the Theravada teachings and adds Bhodisattva activity on top. Here one realises that he is only one, and the others are many. On the path of the Bhodisattva, we develop a vast intention to care for the happiness and well being of all sentient beings and begin our work centred on others. On must have a good surplus to do this. On the Mahayana path, full enlightenment is the goal, however not just for the individual practitioner but for all beings. With the powerful motivation of focusing on all being enlightenment may take several lives.
Vajrayana or sometimes called Tantrayana Buddhism spread north into Tibet, Mongolia and onto Japan. It is of great importance to note here that Tantra is not the exotic sexual path sold in the sixties by hippies and money hungry gurus. Tantra actually means to weave, one must weave all the teachings of the Buddha into one’s life during work rest and play. On this path, one requires great confidence and a firm foundation of the other two paths. The confidence one requires is that if the Buddha, also a human, could reach enlightenment in one life, so can I. When one attempts this path a very close relationship with a lama is a must. One cannot travel this path alone, or it is at least not recommended. Refuge in the Vajrayana school is expanded to include the three roots of Lama, Yidam, and Protectors. Lama or teacher is clear as one needs an exemplary example to follow. The Yidam is Tibetan for mind bond or that which ties us to or reminds us of mind and all its unlimited enlightened qualities. One meditates on a Buddha form that is understood to be an archetypal symbol of these qualities and merges and mixes with it until the qualities are realised or woven into one’s life. The protectors are the energies that ensure us the best conditions with which to practice and develop as fast as possible for the benifit of all beings.
At the beginning of my Buddhist path, I met a Theravada practitioner who told me that the Vajrayana path that I was on did not exist. The Tibetans say that you cannot see the peak of a higher mountain from a peak of a lower mountain. It is further said that the aeons and aeons of practice that a Theravada practitioner needs to reach enlightenment means that they will never be enlightened. However, I firmly believe that these three schools are best seen as a flexible package and or a system of personal growth. One can start in one and finish in another and move around as one wants if needed. Although digging deeply in one spot is always a good idea. Even as a Vajrayana practitioner it is useless to have an amazing roof for a house with no walls or foundation to hold it. Neither of the three paths are superior to one another only that the individual practitioner has a better understanding or personal access to one or the others. One path might not even exist without the others by itself. They are a continuity in and of itself.