A doubly linked list is a type of data structure that consists of a sequence of nodes, where each node contains three components: a data value, a pointer to the next node, and a pointer to the previous node. This allows traversal of the list in both directions—forward and backward—making it more flexible than a singly linked list, which only allows traversal in one direction. In a doubly linked list, adding or removing nodes is efficient, as it only requires updating a few pointers. This structure is commonly used in applications like deques and navigation systems, where bidirectional traversal is beneficial.