The 7th house represents who you are while in relationships with others, whether it's through dating, marriage, business or partnerships of any other kind. Also, contracts and legal agreements.
This house is more about other people than it is about you -- how others react to you and interact with you, be they friends, colleagues, lovers or spouses. Libra, the horoscope sign of partnership and balance, fittingly presides over the 7th house, promoting equality and bringing harmony to your life through those closest to you.
Your birth chart is divided into 12 "houses" which govern specific areas of your life. At the time of your birth, each planet was located in a particular astrological sign and in one of the 12 houses.