1) Why Amazon 2) Background questions (What you did, what research, what challenge). 3) When you click submit, what happened underneath web browser 4) What’s the connection between web browser and server 5) What’s the difference between process and thread 6) In what case using multiple processes and what case using multiple threads. 7) Tell something about tree 8) BFS 9) Writing code, find the number occurs odd times in an array.

OA contained 2 coding questions and then followed by a multiple choice question on behavioral where they emphasized a lot on their leadership rules which you can find on their website