Is Machine Invasion really possible?

Hello! So today I read this very interesting thing on Internet and I wanted to hear other opinions. The machines and applications that are being developed these days, they are very much capable to make their own decisions and sometimes make decisions for us too like Siri etc. So with the passage of time we are making machines which have their own capacity to make decisions and to be more simple, they have the ability to think. Is it possible that sometime in future machines may start rebelling against human race and a strange kind of war between humans and machines, it is possible right? A lot of influential people like Bill Gates have said that it is actually a possibility.