data structures using start (biologyroll no marks next start marks - (biology (afigure next roll no - ( (astudentslinked list and (blinked list after the insertion of new student' record we have seen that every linked list has pointer variable start which stores the address of the first node of the list likewisefor the free pool (which is linked list of all free memory cells)we have pointer variable avail which stores the address of the first free space let us revisit the memory representation of the linked list storing all the studentsmarks in biology nowwhen new student' record has to be addedthe memory address pointed by avail will be taken and used to store the desired information after the insertionthe next available free space' address will be stored in avail for examplein fig when the first free memory space is utilized for inserting the new nodeavail will be set to contain address this was all about inserting new node in start an already existing linked list nowwe will next marks roll no discuss deleting node or the entire linked (biologylist when we delete particular node from an existing linked list or delete the entire linked listthe space occupied by it must be given back to the free pool so that the memory can avail be reused by some other program that needs memory space the operating system does this task of adding the freed memory to the free pool the operating system will perform this operation whenever it finds the cpu idle or whenever the programs are falling short of memory space the operating system scans through all the - memory cells and marks those cells that are - being used by some program then it collects all the cells which are not being used and adds figure linked list with avail and start pointers