From friendly smiley ... emoji, which features a hand with the pinky and index fingers extended, and signals 'rock on'. However, the addition of the thumb actually completely changes the meaning.

Of the six billion emoji that are sent globally every day, around 70% are emotion based – for example, smiley face, love hearts. A smaller proportion of the emoji sent are sad expressions.

Over time, emoji meanings have become subjective, depending on a message's context and wider cultural trends. Which shaking smiley face should you use? Is there a difference between each ...