What is truth?

One person's truth in a lot of cases is not another person's truth, that is why it is so difficult to define the "real" truth. But after thinking about it for a little, I came up with the conclusion that truth can be classified. First there is the concrete truth, scientific truth, that pretty much everyone agrees on. For example, that 2+2=4 or that using the quadratic formula on an equation will tell us what x equals to. There are many truths from that category that we still don't know, and often times that type of truth changes changes with time as scientists make more discoveries, but for the time being, everyone agrees on it. The second type of truth is the type that a large group of people believes in. Examples of that are certain religions and cultural beliefs. For example, catholics believe that all the stories told in the Bible are complete truth, but there are many others who don't. Another example would be cultural superstitions, in Japan a lot of people believe that if they cut there toe nails at night they will not get to be by their parents' side when they are dying. And finally the third type of truth is when a person is convinced something is the reality and the truth in a specific situation and another person believes something else is the truth in that situation. It's when each individual has a different view point because of the different things in their life that they have been exposed to, which have influenced the type of person they have become and their thinking process. I guess I would call that type of truth a personal truth, when you might be totally wrong according to many people but in your eyes you are seeing the truth and they just cant see reality.