Since ancient times, humans have tried to divine the future by reading the stars and planets. This practice is known as astrology, from the ancient Greek word ástron, meaning "star, constellation," and -(o)logy, meaning "the study of."
The concept of the zodiac, rooted in the Greek for "animal" and related to zoo, is ancient too. It is "an imaginary belt of the heavens, extending about 8° on each side of the ecliptic, within which are the apparent paths of the sun, moon, and principal planets. It contains 12 constellations and hence 12 divisions called signs of the zodiac." Each sign has its own symbol (taken from what the ancients likened the constellation to), such as Scorpio ♏ (October 24–November 21).
Put simply, being born at different dates of the year means the sun is at different points along the imaginary belt corresponding to different constellations and their signs. Astrology maintains the sign you're born under influences your character and personality.
The 12 zodiac signs—and 13, if you include Ophiuchus—got a modern upgrade when they were included as computer characters under Unicode in 1993 and organized under its Emoji 1.0 in 2015. Let's see where these symbols come from, what they mean, and how your fate is—allegedly—written in the stars.