1. Linked list :  A linked list, or one-way list, is a linear collection of data elements, called nodes, where the linear order is given by means of pointers. That is, each node is divided into two parts : the first part contains the informations of the elements and the 2nd part , called the linked field or nextpointer field, contains the address of the next node .

2. Free storage list : Together with the linked lists in the memory, a special list is maintained which consists of unused memory cells. This list , which has its own pointer, is called the list of available space or the free-storage list or the free pool.

3. Garbage collection : The operating system of a computer may periodically collect all the deleted space onto the free-storage list. Any technique which does this collection is called garbage collection. Garbage collection usually take place in two steps. First the computer runs through all lists, tagging those cells which are currently in use, and then the computer runs through the memory, collecting all untagged space onto the free-storage list.

4. Overflow : Sometimes new data are to be inserted into a data structure but there is no available space. The situation is called Overflow.

5. Underflow : The term underflow refers to the situation where one wants to delete data from a data structure that is empty.

6. Header link list : A header linked list is a linked list which always contains a special node, called the header node, at the beginning of the list. There are two kinds of header linked lists.

    (a). Grounded header list : A grounded header list is a header list where the last node contains the null pointer.

    (b). Circular header list : A circular header list is a header list where the last node points back to the header node.

7. Two-way list : A two-way list is a linear collection of data elements, called nodes, where each node N is divided into three parts :

    (1). An information field INFO which contains the data of N.
    (2). A pointer field FORW which contains the location of the next node in the list.
    (3). A pointer field BACK which contains the location of the preceding node in the list.