Emojis are simply non-verbal cues in online communication.
Many psychological studies show that meaning is communicated largely through non-verbal cues. In 1971, a study by Albert Mehrabian indicated that the extent to which this was true was far higher than expected - with verbal communication accounting for just 7% of communication. Mehrabian's study revealed that the other 38% of this is vocal (i.e. based on intonation), and the majority - 55% - through body language. With so much of how we communicate therefore dependent on non-verbal cues, emojis are simply performing this role in written messages.
Emojis are a substitute for non-verbal cues in face to face communication. Their significance in digital messages is in clarifying meaning for the recipient. A 2018 study into use and interpretation of emojis found that participants increasingly deployed emojis precisely for this reason: to reduce ambiguity within written communication. Critically, the study showed that emojis bring clarity and nuance to messages, with recipients rarely misinterpreting emojis. In this case, they are hardly changing the face of communication. Rather, they are performing an existing communicative function in a new way.
Emojis can be interpreted in different ways. The Unicode Consortium, which manages the introduction, removal and adaptation of 'official' emojis acknowledges this issue in their own guidelines. They state, emojis are 'encoded in Unicode based primarily on their general appearance, not on an intended semantic.' By virtue of their nature, any meaning given to emojis is flexible and open to misinterpretation. For example, historically many users have deployed the peach emoji to mean human buttocks. When this emoji was redrawn in 2016 to reduce its likeness to the human anatomy, a significant number of users complained to Apple that the critical 'second meaning' had been lost. Emojis are therefore non-verbal cues insofar as they add meaning to written communication. However, they do not perform the same role as body language or intonation, as they have no fixed meaning.
[P1] Face to face communication is largely dependent on non-verbal cues to clarify meaning [P2] Emojis clarify meaning in written communication [P3] Emojis are non-verbal cues in written communication
Rejecting the premises
[Rejecting P2] Emojis do not have a fixed meaning, leaving recipients open to interpret the images in any way they choose