In 1972 the first app went live.

It wasn’t designed for mobile and it was meant only for geeks and programmers.

That invention was designed and built by Ray Tomlinson. Today that messaging app is used by 4.3 billion people and 269 billion messages are sent every 24 hours.

You may have already guessed what that app is.

Email was the first addictive digital technology that had us checking in to our computers and then decades later our mobile phones.

One of the key reasons for why it is so addictive is “operant conditioning”. It is based upon the scientific principle of variable rewards, discovered by B. F. Skinner (an early exponent of the school of behaviourism) in the 1930’s when performing experiments with rats.

The secret?

Not rewarding all actions but only randomly.

Most of our emails are boring business emails and occasionally we find an enticing email that keeps us coming back for more. That’s variable reward.

That’s one way Facebook creates addiction.