Logic has been defined as the study of the rules of correct thinking. It concentrates on the principles that guide rational thought and discussion. The most fundamental concept in logic is that of an argument. An argument must be distinguished from "arguing", which is a debate or disagreement between different people. The logical concept of an argument is: a set of statements, one of which is the conclusion , the others are premises, and the premises support the conclusion. In other words, it is a statement along with the evidence that supports it.
Logic plays a key role in philosophy. If there is going to be any rational discussion of different philosophical positions, the discussion must use the rules of logic. While logic will not specify what the content of the statements are, it will tell you how to arrange the statements in a logical fashion.