Ok, so you started seeing the emoji emoticons in tweets and would like to know how to do it?

Use the following keyboard combinations:

MAC: Command + Ctrl + Space

PC: More complex here, if you use Chrome, get the the free /chrome.google.com/webstore/detail/chromoji-emoji-for-google/cahedbegdkagmcjfolhdlechbkeaieki/details?hl=en-GB” title=”Chromoji plugin” target=”_blank”>Chromoji plug-in, which will let you view, copy and paste Mac-style emoji easily.

Use Emoji emoticons in Twitter Desktop

Prefer another browser? Woe is you: You’ll need to connect your Twitter to an app like iemoji.com,

Source: http://www.washingtonpost.com/blogs/style-blog/wp/2014/04/14/how-to-use-emoji-on-twitter/