Survival guide for Radare2 with practice

I will make several tutorial to explain how to use radare2 for the most common things. I'll try to add more to cover the most possible by the end.
Here is the program :

• crackme1
• Visual Mode (to come)
• Simple Stack Overflow without ASLR (to come)
• Ret2Libc without ASLR (to come)
• Heap Overflow without ASLR
• Radare2 cheat sheet