The dictionary definition of the suffix ism is, "a movement, doctrine, or system of belief as accepted by a group of people." By this definition Buddhism would be a movement, doctrine, or system of belief accepted by what we call Buddhist and expounded by a man we call The Buddha. However this can be somewhat misleading. One could come to believe that the Buddha was preaching of some alternate reality that we must come to believe in. In this way he is seen as a God of sorts. In order to better understand the Buddhist path we have to develop some understanding of the Buddha.
The title Buddha is generally applied to the historical man Siddhartha Gautama, also known as Shakyamuni, in accordance with his family's clan. He was an Indian prince born in present day Lumbini, found on the Indian-Nepalese border. So why is the title of Buddha attributed to this man from Lumbini, India? Shakyamuni first saw that discontentment was a consistent aspect of his and others life. Next he inquired into the cause of this suffering. After he realized that the cause of our pain was created, he concluded that it could be destroyed. Finally he practiced the method for destroying suffering and it's causes. At this point Shakyamuni attained the state of perfect enlightenment, he was fully awake. The term Buddha means simply, "awakened one." Therefore the teachings of the Buddha are really a tried and tested method for becoming fully awake. The Buddha's path is one of purification not one of change. We go from sleep walking to wide awake, from a zombie to a Buddha.
One might ask what are we waking up to? It should be noted that we do not really change our essence or acquire some new qualities, we just wake up to our true nature. Garab Dorje said, "The nature of mind is that of a Buddha from the beginning." We wake up to our true nature not by becoming something else or adding something. Meister Eckhart, the 13th century German-Christian mystic said, "Spirituality is growth by subtraction." We realize the true nature of mind by purifying ourselves of all the crap which had concealed us from things as they are. Therefore one would conclude that the Buddha's teachings are a method for realizing our already existing potential. As said earlier, the difference between a Buddha and you is the difference between being awake and asleep.
All beings already posses the primary cause of enlightenment, Buddha nature. Sugatagabrha is a Sanskrit word meaning Buddha-nature. Sugata meaning Buddha, and gabrha meaning essence or nature. Although Buddha-Nature is beyond the realm definition or logic it can be pointed at. This essence could be said to have three aspects. First it is vast, open, unobstructed space, and is likened to the sky. Second, it is perfect luminosity, perfect clarity, pure "isness". This isness is similar to a mirror as it simply reflects things as they are. Finally it is consistent, continuous energy, without beginning, middle, or end, it has no birth or cessation. This is explained by saying that since it is uncreated, it would follow that it is indestructible. This essence permeates everything and has been with us from the beginning.
It can be difficult for us to recognize this potential in ourselves, because our mind is clouded with anxiety, resentment, past experiences, expectations, disappointments, etc. However in the same way that the nature of the sky remains unchanged on a cloudy day the true nature of mind has remained unchanged by all these clouds. There is also the analogy of a diamond. If you were to take a perfect diamond and bury it in the mud its essence would remain unaffected. We could retrieve the diamond, clean it off, and see that the diamond's nature remained unchanged. The Buddhist path of meditation is nothing more than a method for realizing the diamond and cleaning it off or purifying it. The way of meditation from the Buddha's point of view is a way of unknowing all the crap which prevents us from knowing our true nature, that of a Buddha.