Emoji Understanding and Applications in Social Media

Pictographs, commonly referred to as “emoji,” are a popular enhancement to electronic communication. Emoji are widely used to express sentiment, emotion, and sarcasm across all major social media platforms. In 2018, Facebook reported that people share over 700 million messages with emoji every day, and another 900 million daily emoji-only messages are sent on Facebook Messenger. In the same year, Twitter reported processing 250 million emoji per month. In 2015, Instagram reported that nearly half of the comments posted on photos contain emoji. Social media data have been used to study how emoji are used across different languages, cultures, and user communities and as features to train machine learning models to solve problems spanning many applications. However, the pictorial nature of emoji, that (the same) emoji may be used in different contexts to express different meanings, that the same emoji may be rendered differently