You can bring almost anything that isn't a liquid or gel (or gel/paste like consistency). We always fly so go to snacks for us are goldfish crackers, whole pieces of fruit or apple slices, granola bars, beef jerky, dry cereal. My husband needs something more substantial so he will buy a bagel with cream cheese and a drink before an early flight. I'm pretty good with just coffee in the morning. Each of my three kids has their own backpack with snacks. They like picking them out and getting something special before a big trip.