They are by far the largest plant species in the world and the largest living organism by volume. They are super interesting to study and exhibit some cool adaptations. They are so large that roads can be cut through them and they can actually support life on their limbs, other plants can grown on them. To truly appreciate how big these trees can get you have to see it in person. They are found in the Sierra Nevada, California. the largest of these trees is General Sherman (They have cool names too btw).
You can actually buy a sequoia seed if you are interested in owning your very own giant tree. It will take a couple hundred years for it to mature but still really cool