This character is a Other Symbol and is commonly used, that is, in no specific script.
The glyph is not a composition. Its East Asian Width is wide. In bidirectional text it acts as Other Neutral. When changing direction it is not mirrored. U+1F62E offers a line break opportunity at its position, except in some numeric contexts.
The CLDR project calls this character โface with open mouthโ for use in screen reading software. It assigns these additional labels, e.g. for search in emoji pickers: believe, face, forgot, mouth, omg, open, shocked, surprised, sympathy, unbelievable, unreal, whoa, wow, you.
This character is designated as an emoji. It will be rendered as colorful emoji on conforming platforms. To reduce it to a monochrome character, you can combine it with Variation Selector-15: ๐ฎ๏ธ See the Emojipedia for more details on this characterโs emoji properties.
On Youtube this character is sometimes wrongly displayed as U0001f62e.
The Wikipedia has the following information about this codepoint:
Surprise () is a rapid, fleeting, mental and physiological state. It is related to the startle response experienced by animals and humans as the result of an unexpected event.
Surprise can have any valence. That is, it can be pleasant/positive, unpleasant/negative, or neutral/moderate. Surprise can occur in varying levels of intensity ranging from very surprised, which may induce the fight-or-flight response, or slightly surprised, which elicits a less intense response to the stimulus.
Surprise is included as a primary or basic emotion in the taxonomies of Carroll Izard and Paul Ekman. According to these perspectives, surprise is evolutionarily adaptive, and also innate and universal across human cultures.