Convergence is a critical concept in the field of artificial intelligence, particularly in machine learning and optimization algorithms. It denotes the phase where an algorithm, typically a learning or optimization algorithm, reaches a state where further training with additional data does not substantially change its parameters or performance. This is often an indicator that the algorithm has effectively learned the underlying pattern it was designed to model. In practical terms, convergence assures developers and practitioners that continuing the learning process would yield diminishing returns, hence it is a key factor in deciding when to halt training. Convergence can occur in various forms, such as in gradient descent algorithms used in neural networks where the loss function reaches a minimum, or in genetic algorithms where a satisfactory solution is achieved.

Historical overview: The concept of convergence has been foundational in statistics and mathematics long before its application in AI, but it began playing a critical role in machine learning as these techniques became prominent, particularly from the 1980s onward.

Key contributors: The development of theories and practical methods around convergence has been influenced by numerous researchers in the field of computational mathematics and machine learning. While no single figure can be credited exclusively, the work in optimization by researchers such as Stephen Boyd, Lieven Vandenberghe, and others have significantly advanced the understanding of convergence within the context of AI.