Gradient Descent is pivotal in the field of machine learning for optimizing the parameters of models such as neural networks. It works by calculating the gradient (or derivative) of the cost function with respect to each parameter in the model, which indicates the direction in which the function has the steepest rate of increase. By moving in the opposite direction, the algorithm iteratively adjusts the parameters to minimize the cost function. This process is repeated until the algorithm converges to the minimum. Gradient Descent is crucial for training models efficiently and effectively, especially in high-dimensional spaces where analytical solutions are infeasible.

Historical overview: The concept of Gradient Descent has been around since the early 19th century in the context of calculus. However, its application to machine learning and neural networks began to gain prominence in the late 20th century, especially with the rise of backpropagation in the 1980s, which relies on gradient descent for parameter optimization.

Key contributors: While the basic principles of gradient descent stem from the work of mathematicians like Cauchy in the 1840s, its application and popularization in the context of AI and neural networks are largely attributed to researchers like Werbos, Rumelhart, Hinton, and Williams, who developed and refined the backpropagation algorithm in the 1980s.