Gemini
Gemini is the zodiac sign for people born between May 21 and June 20. Element: air; modality: mutable; ruling planet: Mercury. The cusp dates shift by a day from year to year, so if you were born near a cusp, check your sign with the calculator.
Personality
Gemini is the sign of information and exchange. Geminis pick things up quickly, explain easily and can keep up a conversation with anyone about anything. To them, boredom is worse than trouble.
Strengths: curiosity, mental agility, sociability, the ability to see a situation from several sides at once.
Weaknesses: superficiality and inconsistency. Geminis take on five things and finish one, and in an argument they change their position as they go, sometimes genuinely without noticing.
The Gemini man and woman
The Gemini man is witty, easygoing and unpredictable; he falls for an interesting conversationalist and gets bored with predictability.
The Gemini woman is lively and sociable and needs conversation and novelty; a silent partner feels like a wall to her.
Career and money
Anything involving words and information suits them: journalism, teaching, sales, translation, marketing, IT, brokering.
Geminis earn money in several ways at once and spend it just as variously. Financial discipline is their weak spot.
Compatibility
Traditionally, the easiest matches are signs of the same element and of compatible elements; for Gemini these are Aries, Leo, Libra and Aquarius.
The most challenging are signs in square and in adjacent positions: Taurus, Cancer, Virgo and Pisces. The opposite sign is Sagittarius: strong attraction and an equally strong struggle.
These are general rules of aspects, not a verdict. Each pair is covered separately in zodiac compatibility.
The sign in the birth chart
Your Sun sign is just the position of the Sun at the moment of birth. A full birth chart also includes the sign of the Moon (emotions), the Ascendant (first impression) and the positions of the other planets.
That's why a person may "not seem like an Aries": they have an Aries Sun, a Cancer Moon and a Libra Ascendant, and what comes across is nothing like a Martian manner. Horoscopes in the media work only with the Sun sign, hence the feeling that they aren't about you.