Kangaroo paws in the wild come in a variety of sizes from dainty little catspaws to others up to two metres in height. Those grown in gardens are usually hybrids developed from Anigozanthos flavidius, the yellow kangaroo paw (which is endemic to the south west of Western Australia) crossed with other tall varieties or with the smaller and shorter lived catspaws to produce numerous colours ranging from pale to strong yellows through to many shades of orange and on to reds which range from light and bright to deeper colours like burgundy. There's even a lavender coloured one.
There is one other closely related species of kangaroo paw, also endemic to the South West. This is the black kangaroo paw, Macropidia fulginosa, which has stunning green and black flowers, but it is harder to grow and difficult to propagate so is less widely grown in the garden.
It's quite extraordinary how the kangaroo paw has become such a widely grown plant. When I was growing up when you said kangaroo paw you most likely meant the Western Australian State floral emblem, Anigozanthos manglesii or the red and green kangaroo paw which only grew in the bush. and is still my favourite. Anyone who went bushwalking knew there were other kinds but most weren't as spectacular. When I was a child a favourite family picnic place was bushland surrounding an abandoned gravel pit. Just over the road from it was a cleared paddock on a hillside. I don't know what it was used for because I never saw animals grazing there but every spring the whole hillside would burst into red and green as the kangaroo paws flowered. Sadly it has all been ploughed up now and with that the rhizomes of the kangaroo paws have been destroyed.
You can read more about growing kangaroo paws here. I recently planted some Anigozanthos manglesii in a pot. My fingers are crossed that they'll survive the ink disease that has wiped out all my previous attempts to grow them and which they are notorious for getting and that I'll get some flowers. If I do I'll post them.