So what constitutes a carry-on bag on most airlines?

Officially, you’re allowed one carry-on bag and one personal item.

But what about some other carriers like Spirit and Frontier that charge for even small carry-on bags?

Some travelers have chosen to wear their luggage — using large, oversize jackets with as many as 30 pockets to cram everything inside and simply walking on the plane.

Then, there’s the pillow case approach. It’s not officially a carry-on bag.

But passengers now are filling pillow cases with their clothing and carrying the pillow case on board. And if you think your checked bags might be overweight, then the empty pillow case comes in very handy at ticket counters to lighten the load.