Emoji are prominently used in reacji responses.
- Aaron Parecki includes emoji characters in note and photo contents, and outputs the raw emoji characters in the HTML rather than replacing them with images. Examples:  
- Aaron Parecki's posts show a different profile picture depending on the emoji used in the post. more info: Emoji avatars for my website
standardized vs platform-specific display
Many silos standardize their emoji display by replacing them with the same image on all platforms. (e.g. WhatsApp, Twitter, Telegram, Threma). Replacing them with images also allows to show colored emoji everywhere, which is very difficult using fonts, since there are conflicting standards for multi-colored glyphs. Several permissively-licensed image sets are available, e.g. by Twitter, Emoji One and Google. If a site replaces emoji with images, it should set the alt="" attribute to the text version of the emoji.
Emoji are rendered differently on different platforms, devices, and operating systems, with some examples leading to differing interpretations of the same emoji, depending on how they are displayed to the user.
Sometimes these differences can be stark enough to cause a miscommunication between senders and readers.
- "We, the people of the internet, deserve a hug emoji that is solemn and sympathetic and doesn’t look like you’re mocking the person with jazz hands 🤗" @AstroKatie August 29, 2020
may harm accessibility
Many people have begun to put large strings of emojis into usernames. Accessibility experts argue those who use screen readers must get through verbal explanations of each emoji in a field that was designed for a name and not biographical information. See tweet
https://eev.ee/blog/2016/04/12/apple-did-not-invent-emoji/ Good overview over the history and differences https://socializzed.com/en/blog/socialeaks/dp-211sw-emoji-rosetta-stone The first emoji set for a mobile phone in 1997
Emoji were originally associated with cellular telephone usage in Japan, but now popular worldwide. The word emoji comes from the Japanese 絵 (e ≅ picture) + 文字 (moji ≅ written character).
- Emoji Cheat Sheet
- Unicode Emoji list (warning, this page is 37MB)
- emoji-php-comparsion script that compares php emoji detection libraries and reports results
- Gitlab on using native Emoji with fallback for unsupported ones (complicated!) https://about.gitlab.com/2018/05/30/journey-in-native-unicode-emoji/
- https://javier.xyz/emoji-to-scale/ a clever visual list of emoji in ascending order of scale