A* search is a popular algorithm used in computer science for finding the shortest path between two points on a graph. It combines features of both Dijkstra's algorithm and Greedy Best-First Search, using a cost function that considers both the distance traveled and an estimated distance to the goal. This allows it to efficiently explore paths that are likely to lead to the best solution. The algorithm maintains a priority queue of nodes to explore, prioritizing those with the lowest total estimated cost. By continuously updating this queue, A* search ensures that it explores the most promising paths first, making it effective for applications like navigation systems and game development.