Sorry to butt in on this one,
@pkondz, but it caught my attention because I just happen to be eating a scoop of my homemade strawberry rhubarb crisp here as I'm reading this. (Soo very fortunate that strawberries and rhubarb happen to be in season at almost exactly the same time!!) Rhubarb is a plant with really long green-to-red leaf stalks below its big floppy green leaves. You eat the stalks, but not the leaves, which aren't safe to consume. It's technically a vegetable, I think, but it's usually paired with fruits. The closest thing I can think of that's similar to the stalks would be celery, but the flavour is very different, and the shape/texture are a bit different as well. It's quite tart, so it's cooked more often than used raw. That said, I grew up with it growing behind my grandmother's house, and we would regularly go out and pick it, fill the bottom of a drinking glass with sugar, suck the end of the rhubarb, and then stick it down in the sugar, before crunching the end off....then repeat! It pairs really well with strawberries and sugar, though, and is commonly used in pie filling, or similar kinds of desserts. If you like a balance of tart and sweet, it's really tasty, and fresh-tasting for early summer.