Buddhism can be defined as the true state of the nature of the world, or as the Buddha’s teachings.
In the first definition, Buddhism is a path of practice and spiritual development to gain insight into the true nature of reality or enlightenment. An enlightened being sees the nature of reality absolutely clearly, just as it is, and lives fully and naturally in accordance with that vision. This is the goal of the Buddhist spiritual life, representing the end of suffering for anyone who attains it. Buddhist practices like meditation are means of changing yourself to follow the path in order to develop the qualities of awareness, kindness, and wisdom leading to Enlightenment or Buddhahood.
In the second definition, Buddhism is the teachings of the Buddha. The teachings inspire us to take responsibility for our own lives by understanding cause and effect (karma). Buddha explained in great detail how we shape our future through our thoughts, words and actions. In Buddhism, compassion and wisdom go together. When we act from compassion, focusing on others rather than ourselves, the disturbing emotions that we all have, like anger, pride, attachment, and jealousy, loosen their grip, and wisdom has a chance to appear spontaneously. The teachings are beneficial in three achievement levels, depending on the particular practitioner:
1) Beneficial for this life and future lives,
2) Beneficial for liberation from cycles of rebirth which ends suffering (this is the highest aim of the Theravada tradition), and
3) Beneficial for the highest goal of Buddhahood (this is the highest goal of the Mahayana tradition).