An epoch is a significant period in time marked by notable events or developments. In geology, epochs are subdivisions of periods in the geological time scale, helping scientists understand Earth's history. For example, the Holocene epoch began around 11,700 years ago and continues to the present day, characterized by the development of human civilizations. In the context of machine learning, an epoch refers to one complete pass through the entire training dataset. During each epoch, the model learns from the data, adjusting its parameters to improve accuracy. Multiple epochs are often needed to achieve optimal performance, as the model refines its understanding with each iteration.