You must have heard Aries, Taurus, Gemini, etc. These are name of zodiacal signs, not stars. In the context of popular culture, they just represent tropical sun signs. Although, one sign does not mean horoscope, but this is a common misnomer. The sun stays in a tropical sign for a month. It’s a small part of modern western astrology. The sun sign is a generalized and handy mean for pinpoint personality traits, but it cannot be relied upon for delineations and predictions. In a horoscope (whether it is western or Indian), the degree of rising sign i.e. ascendant is the most important determinant that fixes the house placement of all planets.