Data structure is logical or mathematical organization of data. It describes how to store the data and access data from memory. Actually in our programming data stored in main memory(RAM) and To develop efficient software or firmware we need to care about memory. To efficiently manage we required data structure.There are two different types of data structure. In linear data structure data elements stored in sequential manner. Stack Queue and Linked List are the types of linear data structure. In Non-Linear data structure data elements are not stored in the sequence manner. Tree and Graph are the type of non-linear data structure.