I didn't know that! My sister-in-law lined the oven at her church with aluminum foil to make clean-up easier. It melted onto the bottom plate (?) of the oven and pretty much ruined it. The plate will have to be replaced, though we've heard that it's not too expensive.

People always lined their ovens with foil, but perhaps most ovens are self-cleaning now..I don't know, but the Reynolds Wrap people advise NOT to line the bottom of the oven for that very reason. They say to line the rack if you want, but not the bottom of the oven.

I didn't know that, and would have been apt to make the same mistake myself. Live and learn.

There are also liners you can purchase at the grocery store (where the foil and aluminum bakeware is located). I bought several and keep one on the bottom rack in my oven. If something drips or spills over it's caught by this liner.

I just stick a foil lined cookie pan on the lower shelf underneath whenever I make something I'm worried will spill or cook over the sides of the dish it's in. If it spills, it lands on the cookie pan and all I have to do is let the cookie pan cool off and take the foil off and toss it.