All pulses and lentils are forms of legumes. The main differences are in the ways the crops are harvested, stored, and eaten. Legume - Wikipedia. This article gives lists of different legumes and how they are used. It is quite a lengthy article and gives a lot of information, but in the end, the biggest difference between legumes, whatever they are called and however they are used, is that legumes fix nitrogen in the soil when they are grown. This enriches the soil for future crops.