What is the difference between cereal and a cereal product?

Cereals are crops that are highly rich in carbohydrates i.e all cereals are mainly classified as carbohydrate foods...cereal foods are mostly in "grains"(e.g maize,rice,guinea corn e.t.c) on the other hand legumes are dry dehiscent fruits(i.e fruit that easily releases it's seed(s).) that is to say any plant that contains easily-splited-seeds in its pod(s) is a legume..e.g beans,peas,cowpea,groundnut,pride of Barbados e.t.c