A linked list is a linear data structure that stores multiple values in nodes that are connected by pointers. Each node contains a data field for its value and a pointer field linking to the next node. This allows flexible and efficient insertion and removal of nodes anywhere in the list. The document outlines the basic structure of a linked list and node, and provides pseudocode for creating a new node by allocating memory, inserting the data value, and initializing the next pointer to NULL.