Current horoscopes are from Western astrology which in turn r derived from Babylonian astrology. Babylonian system was developed to predict the “mood” or intentions of gods
the sky is divided in 12 parts where the sun travels across the sky( In those days it was believed sun rotates around the earth ) in reality it was earth’s rotation around the sun. These 12 sections were named and collectively called zodiac signs.
It’s pseudo-science at best. A sort of guess work. The basic idea is that universe is alive and so is man. So whatever happens in the universe will also happen in man (microcosmos-macrocosmos analogy) in other words, nature of human and universe is similar so if we can predict what going to happen in the universe then we know what will happen to man. That’s why sky is mapped and divided in 12 imaginary sectors.
Astrology/horoscopes were very prevalent in Hindu, Chinese and Tibetan cultures as well. It’s very complicated system because it attempts to explain human behavior and hence attempts to predicts future events. There r many different systems of astrology and each is further divided in many schools in every culture.
If u attempt to predict randomly, u r correct 20% of the time. Astrology predictions r also true in the same range but human psyche only focuses on the correct predictions so many many people believe it to be true (the practice of matching Janam Kundlee in Hindu culture)
This is the very basis of horoscopes, now u can decided if it’s Islamic or not