By this project, I learn how to work with wires and photon. I get the original idea from others which want to monitor mailbox. But, it didn't work on my project cause they are monitor whether and when the door of mailbox has been opened. It is not reasonable. Finally, I find a right sensor and solved this problem. I am so proud of what I have done in this project. I solved a small problem in practice using IOT products which I learned from class. A very exciting experience!