Hello everyone, I just joined the community and am excited to get to know and work with all of you. Good luck to all of you on your journey.

I'm pretty confident that this is right. Codepen has been going a bit bezerk. Can you just confirm that this is correct so I am not missing anything? https://codepen.io/Ryan-Pickard/pen/MWMaRwL?editors=0012 line 326

Ok...so looking at like 340... I have the function that executes the map method and it passes the first test, but on the second test the index that is passed and my code is returning not a number. Callbacks take the index as the second value in the callback, so I'm confused why my code isn't working. In this instance, "i" is the index. Any ideas what I am missing here? https://codepen.io/Ryan-Pickard/pen/MWMaRwL?editors=0012

If you look at line 160 (_concat), with the third test, the first value bring passed in the function isn't passing through. You'll see the letters1._concat get passed, then you'll see the array [2,3], but the 1 that is inserted prior to the [2,3] isn't getting concatinated --I know I'm probably explaining this bug like shit, but can you take a look and let me know what I am missing here? https://codepen.io/Ryan-Pickard/pen/MWMaRwL?editors=0011

Dude... Take this away from me! lol https://codepen.io/Ricecakes_95/pen/gOyzNGB?editors=0012