Accdg. to my own definition, it is the art of controlling oneself from technology. E.g. don't use your phone when talking to someone, learn to turn off your gadgets when it is time to sleep.
What I mean is, technology makes us anti-social and sometimes becomes a great distraction. I see some people use their phones instead of talking to people. Chatting is not always okay because you don't know what the person is really going through or what is the real reaction. Compare it to personal talking, you get to see his/her reaction to what you said and you get an immediate reply. Imagine this, when you're talking to someone then the person you're talking to uses his/her phone, then you will surely lose interest in talking to him/her because of the phone. And this applies to you too, the other person will lose interest in talking to you when you use your phone while talking. Except, that is, when what you're talking about includes usage of phones. Then that is perfectly normal!
Learn when to use your devices. These things can and will destroy you if you allow them to be your way of living life. Here's a video I found on the web that tells something about technology discipline: