What does "tin" mean?

I'm working in a grocery shop.

We sell some breads here.

I just wonder what 'tin' means with the bread in this case?

You should use the question format rather than notebook entries for this.

If you were in a shop that baked bread ( a bakery shop - rather than a grocery shop) - a tin might be the container than the dough mixture is in while it is baked. Not all breads are baked in a tin but some are.