RMCDE stands for Recursive Maximum Cardinality Edge Decomposition. It is a type of mathematical problem involving graphs. Graphs are diagrams made of points, called 'nodes,' connected by lines, called 'edges.' RMCDE is a type of problem involving finding the biggest group of nodes and edges that can be created in a graph. For example, if you have a graph with 10 nodes and 15 edges, RMCDE can help you find the largest group of nodes and edges that can be made from the graph.