roll no name aggregate grade next ram distinction shyam first division mohit outstanding rohit varun distinction outstanding karan first division veena second division - meera first division krish kusum third division outstanding silky first division start monica distinction ashish first division gaurav first division figure studentslinked list thuslinked lists provide an efficient way of storing related data and performing basic operations such as insertiondeletionand updation of information at the cost of extra space required for storing the address of next nodes memory allocation and de-allocation for linked list we have seen how linked list is represented in the memory if we want to add node to an already existing linked list in the memorywe first find free space in the memory and then use it to store the information for exampleconsider the linked list shown in fig the linked list contains the roll number of studentsmarks obtained by them in biologyand finally next field which stores the address of the next node in sequence nowif new student joins the class and is asked to appear for the same test that the other students had takenthen the new student' marks should also be recorded in the linked list for this purposewe find free space and store the information there in fig the grey shaded portion shows free spaceand thus we have memory locations available we can use any one of them to store our data this is illustrated in figs (aand (bnowthe question is which part of the memory is available and which part is occupiedwhen we delete node from linked listthen who changes the status of the memory occupied by it from occupied to availablethe answer is the operating system discussing the mechanism of how the operating system does all this is out of the scope of this book soin simple languagewe can say that the computer does it on its own without any intervention from the user or the programmer as programmeryou just have to take care of the code to perform insertions and deletions in the list howeverlet us briefly discuss the basic concept behind it the computer maintains list of all free memory cells this list of available space is called the free pool