macOS What kind of program is this?

http://www.youtube.com/watch?v=1qwpT2etnQ0

just some background info on this. When NIKE releases new shoes they post a link on their twitter page which then brings you to the item page on the nike.com website.

In the video above, this person has developed a program that once nike.com's twitter page sends out a tweet with the item link, he is able to sign on to his nike.com account, select his size, and pay with his credit card all in one action. Can anyone help me with a program like this? or at least explain how it works?

Thank you any help is appreciated.

thank you that helped alot, I also wanted to know how I could created my own php script. Or is that a more difficult task?