Emoji

Emoji was a system of communication with the use of smileys and other pictograms or images.

It was popular on Earth during the 21st century, and remained a popular form of language centuries later, when Gliese 581 D was colonised. It was used by the Emojibots as their primary form of expression. The colonists also wore mood indicators that expressed their emotions in order to better communicate with the robots. (TV: Smile)

Known emoji
Known emoji included the following pictograms:
 * 😃 – smiling face (TV: Smile)
 * 💀 – a skull, used as a symbol for death (TV: Smile)
 * 😢 – crying face (TV: Smile)
 * 💡 – a light bulb, used as a symbol for new ideas (TV: Smile)
 * 😕 – puzzled face (TV: Smile)
 * ❓ – question mark, indicating confusion (TV: Smile)
 * 👍 – thumbs up, indicating approval (TV: Smile)