Black beans are a legume and are similar to red kidney beans. I've never actually used them, but have eaten them and they are very nice with a texture much the same as red kidney beans. I think I have seen tinned ones in our supermarket, but I wasn't taking a great deal of notice so I may be wrong there. As with other legumes, you can buy them dried for soaking and cooking on later (freeze the excess for use in other meals).