non-bread

Back awhile ago, one of my sisters started mentioning something called "non-bread" - I just had a big ? whenever she said it. Okay, if it's not bread, then what is it? Why would you call it by what it isn't rather than by what it is? Even if it's not bread, it could still be practically anything. Confusing.

Then one day, I saw a package of it on the table. Naan bread.

(by the way, naan is a kind of South Asian flatbread and is delicious).