Decision trees are a common technique used in data mining to predict a target value based on several input data. Prediction of output value involves testing of input sample on certain rules. Each terminal node of the tree represents the output to which sample it belongs. To figure out the output, we start at the root node of the tree, and ask a sequence of questions about the features. The interior nodes are labeled with questions, and the edges or branches between them labeled by the answers and based on the attributes you eventually end in a particular leaf.