system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why is Pi so special and how was it discovered?
gpt
Pi was discovered initially as the specific ratio of a circle's circumference to its diameter. They determined that the exact ratio was not a simple fraction, though they were happy to approximate. As they explored mathematics, they determined that this ratio came about with surprising regularity, due to it's natural relation to circles and spheres.