They originate from South and Central America where they grow wild. Domesticated beans are larger; the earliest archaeological evidence of these is from 5500 BC in the mountains of North Peru.
As with so many vegetables the flowers are very pretty. Indeed some varieties are specially bred to produce attractive blooms.
I doubt we shall harvest more than half a dozen handfuls but we're pleased to see any that care to grow and treat them with the reverence they deserve . . . before devouring them . . . ;-)Enough to tease the taste buds . . .