What are the things need to travel domestically from one place to other?

Question

What are the things need to travel domestically from one place to other?

Answer 1

A state id, drivers license, etc...

Answer 2

Different countries have different rules, but in the US:

If you are a passenger on an airline, if you're over 18 you'll need your choice of driver's license, state ID card, or passport

If you are driving, you'll need a driver's license.

If you are a passenger in a car, walking, bicycling, etc. you don't need anything to travel, but once you get to where you're going, you may need a driver's license to, say, rent a hotel room or something.