佛陀(Buddha)，原名悉达多.乔答摩（Siddhartha Gautama）。
活动时期约西元前6世纪～西元前4世纪
印度人的精神领袖和佛教创始人。佛陀的梵语意为「觉悟者」，是他的称号而不是名字，佛教徒相信有无限多个过去的和未来的佛陀。历史上的佛陀（指佛陀乔答摩或简称佛陀）是印度-尼泊尔边境地区的释迦族王国的王子。据说青年时代的悉达多养尊处优，直到有一天他出宫游玩，分别遇见一老人、一病人和一具死屍。他放弃王公贵族的生活，花了七年时间寻找老师，尝试各种极端的苦修生活，包括绝食以求悟道，但结果都不能令他满意。有一天他坐在菩提树下深思冥想，在抗拒了魔的诱惑後，意识到「四谛」，并因而顿悟。佛陀到鹿野苑向他的同伴第一次说法，提纲挈领地宣讲「八正道」，以此提供一条自我放纵与自我禁欲之间的中间道路，引向涅盘解脱。听了这次说法的五个苦行僧成了他的第一批门徒，被接纳为僧伽或佛教等级中的比丘（僧人）。佛陀的使命完成了，在库辛纳拉（现名卡西亚）因意外食用有毒蘑菇而过世，逃脱了再生的轮回；後人将佛陀遗体火化，在他的遗物上建塔供奉。
English version：
Buddha
Indian spiritual leader and founder of Buddhism. The term Buddha (Sanskrit: “Enlightened One”) is a title rather than a name, and Buddhists believe that there are an infinite number of past and future buddhas. The historical Buddha, referred to as the Buddha Gautama or simply as the Buddha, was born a prince of the Sakyas, on the India-Nepal border. He is said to have lived a sheltered life of luxury that was interrupted when he left the palace and encountered an old man, a sick man, and a corpse. Renouncing his princely life, he spent seven years seeking out teachers and trying various ascetic practices, including fasting, to gain enlightenment. Unsatisfied with the results, he meditated beneath the bodhi tree, where, after temptations by Mara, he realized the Four Noble Truths and achieved enlightenment. At Sarnath he preached his first sermon to his companions, outlining the Eightfold Path, which offered a middle way between self-indulgence and self-mortification and led to the liberation of nirvana. The five ascetics who heard this sermon became his first disciples and were admitted as bhiksus (monks) into the sangha or Buddhist order. His mission fulfilled, the Buddha died at Kusinara (present-day Kasia), after eating poisonous mushrooms served him by accident, and escaped the cycle of rebirth; his body was cremated, and stupas were built over his relics.