The Atheist Perspective

This is of minimal concern to naturalism, which doesn't adhere to any of those faith traditions. They are ancient, flawed, and ultimately false, although like most religions, each has something of the truth in it.

In general, Buddhism is an evolution of Hinduism that was imported to East Asia by missionaries. It reflects Hindu thought (karma, for example) and adaptations thereto (such as the spiritual quest to transcend reincarnation through moral and mental conditioning). Confucianism, by contrast, is the oldest and most traditional philosophies of China. It is a pragmatic philosophy about maintaining social harmony and order in the present world, and it places minimal importance on supernatural beliefs of any kind (apart from their social utility). Taoism was a Chinese reaction to Confucianism, promoting a less conservative and more nature-oriented worldview that focuses on understanding and aligning oneself to the Tao, a force that generated and governs the universe. Evolving in reaction to each other, Taoism and Confucianism differ on many matters of morality (e.g. Confucianism endorses the use of force to maintain order, Taoism does not) and the means of acquiring wisdom (e.g. Confucianism emphasizes learning, Taoism emphasizes inner contemplation). They also differ in some points of metaphysics (Confucianism allows the possibility of an afterlife, Taoism does not). But there are also many different sects within each of these faith traditions. Like Christianity, there is no "one" Buddhism, Confucianism, or Taoism, and often those sects within a faith differ from each other as much as the faiths do themselves.

If you want more detail on their respective differences, you will have to explore each one yourself through many diverse readings.

From Taoist to Infidel