What tools do you bring on your daily ride?

Hi, last week I went riding with a group of people on the hills of Iowa... Beautiful place but very isolated. A thought came to my mind... What happens if the bike breaks down and I am by myself in the middle of nowhere?

I am not a great mechanic but I can fix a flat tire or replace a lightbulb... So my question to you is... What tools do you carry with you at all time apart from the standard tools that came with the bike?

Also where do you keep them? Under the passenger seat,or do you have a tail bag?....

Thank you in advance for your time and thoughts...