Gautama Buddha, also known as Siddhartha Gautama, is the founder of Buddhism and is revered as the enlightened one who attained Nirvana after a profound spiritual journey. His teachings focus on the Four Noble Truths and the Eightfold Path, which outline a method for overcoming suffering and achieving spiritual enlightenment. His life and insights have significantly influenced Indian philosophical texts and shaped various schools of thought in Buddhism and beyond.