Emoji were initially used by the Japanese mobile operators NTT Do Co Mo, au, and Soft Bank Mobile (formerly Vodafone).
These companies each defined their own variants of emoji using proprietary standards.
(See also Models of communication.) For example, people in China have developed a system for using emoji subversively, so that a smiley face could be sent to convey a despising, mocking, and even obnoxious attitude, as the orbicularis oculi (the muscle near that upper eye corner) on the face of the emoji does not move, and the orbicularis oris (the one near the mouth) tightens, which is believed to be a sign of suppressing a smile.
The second problem, on the other hand, has to do with technology and branding.
When an author of a message picks an emoji from a list, it is normally encoded in a non-graphical manner during the transmission, and if the author and the reader do not use the same software or operating system for their devices, the reader's device may visualize the same emoji in a different way.
Small changes to a character's look may completely alter its perceived meaning with the receiver.
Some emoji have been involved in controversy due to their perceived meanings.
Multiple arrests and imprisonments have followed usage of gun ( ), as emoji.
Unicode 8.0 added another 41 emoji, including articles of sports equipment such as the cricket bat, food items such as the taco, signs of the Zodiac, new facial expressions, and symbols for places of worship.
(whose Yasuo Kida and Peter Edberg joined the first official UTC proposal for 607 characters as coauthors in January 2009), went through a long series of commenting by members of the Unicode Consortium and national standardization bodies of various countries participating in ISO/IEC JTC1/SC2/WG2, especially the United States, Germany, Ireland (led by Michael Everson), and Japan; various new characters (especially symbols for maps and European signs) were added during the consensus-building process.
Encoding in the Unicode standard has allowed emoji to become popular outside Japan.
The first issue relates to the cultural or contextual interpretation of the emoji.
When the author picks an emoji, they think about it in a certain way, but the same character may not trigger the same thoughts in the mind of the receiver.