Short examination on Faith

What is faith exactly, is it a belief, is it loyalty? People have faith everyday without realization of this fact.

Here are the first three definitions of Faith
1. confidence or trust in a person or thing: faith in another's ability.
2. belief that is not based on proof: He had faith that the hypothesis would be substantiated by fact.
3. belief in god or in the doctrines or teachings of religion: the firm faith of the Pilgrims.

Here is the origin of the word as well.
Origin:
1200–50; Middle English feith < Anglo-French fed, Old French feid, feit < Latin fidem, accusative of fidēs trust, akin to fīdere to trust. See Trust

As a child must trust his parents to feed him, clothe him, and take care of his basic needs why do adults have such a difficult time having trust in something they don't understand, or see? Do you think about God in terms of a religious view? your Christ, or your Catholic God?

Why do most of us think we need to KNOW and UNDERSTAND everything about God in order to be willing to believe that there is some sort of God?