The real function of the horoscope is to explain and predict the current position of the Sun, Moon, signs, celestial spheres, and many other celestial events that happen in the universe for a particular individual at a particular time. It may also be used to explain the path through which the sun or moon will take, and what will happen as it does so. It is usually written on paper as a sort of guide and prediction tool, and can be found in books, charts, diaries, and even computers.
Horoscopes are mostly based on the Chinese concept of elements, especially of the five Earthly elements: Wood, Water, Fire, Metal, and Earth. These are then divided into the four elements - fire (Jing), water (Qi), metal (Yang) and wood (Yin). There are many different kinds of charts, such as those based on the Chinese calendar, solar year, the lunar calendar, and the Bagua. This latter is a complex system of calculation based on the traditional Chinese astrology, which has been developed over several centuries. Horoscopes also reflect the culture and society in which they were originally created, sometimes having special meanings attributed to them depending on their exact interpretation.
Delegating the interpretation of a Horoscope to another party, such as your spouse, is very common. For example, when you look at your horoscope, you can inform someone of some changes you want to make in your life - or vice versa. If you want to go on a diet, you can mention this in your Horoscope, or if you want to change your career, mention this in your Horoscope as well. You can also use the Horoscope to know about the birth times of your parents and grandparents and so on. These are just a few examples that prove that even though there is no direct science behind Horoscopes, they can be used for various reasons.