I carry around only three ID cards: my GA (Swiss train pass), my school ID from my school last year and my provisional ZIS student ID.
These ID cards, first of all, give a timeline of where I have recently lived. My ID from last year is from an American school, and my train pass and ID from this year show that I now live in Switzerland. The fact that I only have three cards also reveals that I don’t like clutter and don’t carry around unnecessary cards. They also tell people my age, name, grade I'm in and what I look like. The fact that I use public transport regularly also becomes evident from my train pass.