title: What is a key in a linked list?
body: <p>Here is a linked list implementation in C. </p>
  
  <p><a href="https://www.tutorialspoint.com/data_structures_algorithms/linked_list_program_in_c.htm" rel="nofollow noreferrer">https://www.tutorialspoint.com/data_structures_algorithms/linked_list_program_in_c.htm</a></p>
  
  <blockquote>
  <pre><code>struct node {
     int data;
     int key;
     struct node *next;
  };
  </code></pre>
  </blockquote>
  
  <p>What is a key in a linked list? It seems to me a key is just another piece of data of a node. What is the point of having a key? </p>