Incremental learning is a machine learning approach where the model learns from new data without forgetting the previously learned knowledge. Population-Based Incremental Learning (PBIL) is a variant of incremental learning that combines the concepts of genetic algorithms and incremental learning. In PBIL, a population of solutions is maintained, and the algorithm iteratively updates the probability distribution of the solutions based on their performance. This allows the algorithm to explore the solution space more efficiently and converge to better solutions over time.