A dequeue (double-ended queue) is a data structure that allows insertion and removal of elements from both ends. This flexibility makes it useful for various applications, such as scheduling tasks or managing resources. Unlike a standard queue, which follows a first-in, first-out (FIFO) principle, a dequeue can operate in a more versatile manner. In a dequeue, you can add or remove items from the front or back, making it efficient for scenarios where you need quick access to both ends. Common operations include enqueue (adding an element) and dequeue (removing an element), which can be performed on either side of the structure.