Speck in my eyeball

Sooo I'm not really sure what it is? It kinda looks scab like in person or a healed over scrape? I'm obviously not gonna pick at it. It doesn't hurt though so I'm not gonna be too worried about it. Just curious as to why it would suddenly appear seeing as I've never had this before, haven't had any irritation in my eyes, or even rubbed my eyes very much other than me washing my face and it doesn't wash out with water or anything so it's not a piece of something I don't think.