There are aspects of astrology which have merits, but a lot of times it is either misinterpreted or inaccurate. The modern astrology horoscopes are generic, the public ones are supposed to apply to a lot of people which means they're generally less accurate. Compatibility charts are only accurate if they correspond correctly to the element groupings.
There are 12 zodiac signs, with 4 elemental groupings. 5th element is considered the whole and as such encompasses all 4 groups.
The 4 elemental groups are as follows;
Fire; Aries, Leo, Sagittarius
Earth; Taurus, Virgo, Capricorn
Air; Gemini, Libra, Aquarius
Water; Cancer, Scorpio, Pisces
Air and Fire elements are within the same preferable compatibility grouping generally. Earth and Water are also considered to be more compatible with Earth and Water element signs in general.
For asian zodiac, things are a bit different, but it also has 12 signs.
This is a very in depth subject, which has various belief systems. Both can be true or neither depending on belief, if its integrated enough.
To take the rational approach, its not totally preposterous to consider that astronomical bodies may influence things on earth, each one has its own frequency range which can be listened to using radio. The moon affects the tides of the ocean and charges in capacitors (although the latter is rarely noticable), as well as beings which have lots of water content in them. The interplay between sun and moon also affects the earth causing earthquakes and other events. While the effects of other astronomical bodies further away may seem less significant to the rational observer, they still seem to be related with various things. Their frequencies do carry over here and their lights are mostly visible in the cloudless night (outside light polluted areas). Making sense of these is what astrology is mainly about.