Kahn's algorithm is a method used to find a topological ordering of a directed acyclic graph (DAG). It works by identifying nodes with no incoming edges, also known as "sources," and removing them from the graph. This process continues iteratively, allowing the algorithm to build a sequence of nodes that respects their dependencies. The algorithm maintains a list of nodes in the topological order and uses a queue to manage the sources. As nodes are removed, their outgoing edges are updated, potentially revealing new sources. This ensures that all nodes are processed while preserving the directed relationships between them.