Buddha

What is Buddha?
A Buddha is a person who has developed all positive qualities and eliminated all negative qualities. Buddha was an "ordinary" human like you and me before he became enlightened. Enlightenment is compared to awakening, as a person suddenly experiences a complete transformation of body and mind from sleeping to waking up. One could say that a Buddha represents the very peak of evolution, as he/she is omniscient or all-knowing.
The Dalai Lama about Buddha
Our teacher, Sakyamuni Buddha, is one among the thousand Buddhas of this aeon. These Buddhas were not Buddhas from the beginning, but were once sentient beings like ourselves. How they came to be Buddhas is this.
Of body and mind, mind is predominant, for body and speech are under the influence of the mind. Afflictions such as desire do not contaminate the nature of the mind, for the nature of the mind is pure, uncontaminated by any taint. Afflictions are peripheral factors of a mind, and through gradually transforming all types of defects, such as these afflictions, the adventitious taints can be completely removed. This state of complete purification is Buddhahood; therefore, Buddhists do not assert that there is any Buddha who has been enlightened from the beginning.
A 1000 Buddha's
The historical Buddha, Shakyamuni or Gautama Buddha, lived about 2500 years ago in India. However, he was not the first Buddha, and will not be the last either.
He taught that during this eon (one billion years), there would be 1000 fully enlightened Buddhas who would introduce Buddhism after it has been forgotten.
29 known Buddhas
There are 29 Buddha's including the expected Maitreya Buddha. The 29 known Buddha's are Taṇhaṅkara, Medhaṅkara, Saraṇaṅkara, Dīpankara, Koṇḍañña, Maṅgala, Sumana, Revata, Sobhita, Anomadassi, Paduma, Nārada, Padumuttara, Sumedha, Sujāta, Piyadassi, Atthadassi, Dhammadassi, Siddhattha, Tissa, Phussa, Vipassi, Sikhi, Vessabhū, Kakusandha, Koṇāgamana, Kassapa, Gautama and Maitreya.
What is Buddha not?
A Buddha is not the creator of the universe, like God in other religions. In fact, there is no creator of the universe in our philosophy.
The Buddha is not omnipotent like God. The simple reason is that if he were, out of compassion, he would have long released all sentient beings from suffering.
The state of a Buddha is not impossible to reach but most likely it may take many incarnations and extensive karma.
A Buddha is not hindered by ignorance, but is all-knowing. A Buddha is not a passive being. He will use his wisdom to help to other living beings when they are open to his advice.