Build an undirected node-and-edge graph by hand or load a preset, pick a start node, then watch hand-rolled BFS / DFS expand step by step with the current node, visited set and live queue / stack highlighted.
Build a graph: in Add node mode click empty space to drop a node; in Add edge mode drag from one node to another to connect them; Move drags a node, Delete removes a node or edge, Set start picks the source. Or load a preset (linear / tree / cycle / grid / random). Then choose a start node and BFS or DFS. Next step advances one operation, Auto play runs the whole traversal at the chosen speed, Reset clears the animation but keeps the graph, Clear graph empties everything. Yellow = in the frontier, orange = current node, blue = visited; the orange edges form the BFS / DFS spanning (discovery) tree. BFS explores layer by layer using a queue; DFS dives deep using a stack. Both algorithms are implemented from scratch.