Marriage compatibility is all about being able to live together with each other after the vows of marriage have been taken. These vows are the basis of trust in the marriage.
Dating is what you do before the marriage before you take the plunge into marriage. It is during the dating that it tells you whether it is the person with whom you will be able to live your life with. Make sure that when you date you gauge from the person's responses as to what kind of importance does he give to marriage and compatibility.
Many people believe in astrology and go in for the love match tests or other sorts of compatibility tests to make sure that they can co-exist with the other person. In astrology each person's nature is defined by a few symbolic things and the movement of the stars. For example in Chinese astrology it is defined 12 year lunar cycle and there are 12 animals which signify a particular type of personality.
In Indian astrology there are 36 signs which are matched against the other persons 36 signs. These 36 signs of the other person are defined by the star under which you were born. Nowadays there is software available to check you compatibility quotient.
Compatibility has a new meaning in today's world. That compatibility has to do with physical compatibility and the genetic compatibility. A lot of people nowadays think that physical compatibility is a must in marriage. A lot of marriages end because of the lack of physical compatibility.
Then there are genetic compatibility issues as well. It is important to check that also as you do not want your progeny to be deformed or have genetic disorders. With advancement in science you can check your genetic make up and see whether it will be compatible with your partners' genetic make up.
On the other hand the there are people who think that no amount of tests can save a marriage and the onus lies on the two individuals to make the marriage work. That said it is all about your beliefs in the marriage system. If you truly believe that two individuals can coexist and can marry each others thoughts and ideas onto each other then you can actually make a marriage work. But if you believe that marriage means that you will not give an inch of space to the other partner then nobody can save a marriage like that.