They are "the convex bone in front of the knee joint; the patella."

So, if you hear someone say that they have scraped their knee(s), please, do the right thing by placing your right hand on their left shoulder and saying in a comforting, yet wise voice: "My friend, you did not scrape your knee(s). (theatrical pause here) You scraped the protective skin that covers your patella(e)." They may thank you. Or, your friend may stop returning your texts. It's chance as to what they decide to do.

i feel dumber having read this.

I feel after having read this

You're still wrong since you want to get super technical. You didn't scrape your knee, you scraped your epidermis.

Or, you know, you could just be a normal person and say yeah you scraped your knee cause that's what you did.

..what

I rarely meet "normal" people. They may appear normal in the beginning, then, as they become comfortable (which could be days, months, or years) with the friendship, they start sharing of their very colourful/quirky past(s) and ideas and goals. People, as far as I can tell, have a difficult time sustaining normal. Think of our species as like sprouting dandelions which are making their way through cracks in the sidewalk. Then these sprouts finally break through the concreate dust, push aside weathered cigarette butts, and draw some nutrients from dry dog feces and out pops a bright yellow flower and its green leaves. We are a strange species when compared to the rest of the life that Earth is host to.

Comparison is the thief of joy.
Enjoy YOUR life because we both know in the grand scheme of things, it's short and meaningless. Do your bestest. I belief in you.

Thanks!

what part of that was confusing to you?

I get it but 10 out of 10 people know where your kneecap is.

"Ow i hurt my anterior cruciate ligament!!" Im sure most people would know right off hand. As shown not covered by the patella but you see what i mean. Ouch i scrapped my body.