Although emoji and emoticons are ubiquitous today, back in the 1990s, what later became a "craze" started with just one simple heart — <3 — thanks to Japanese telecom company NTT DoCoMo. Users of DoCoMo's pagers could send a <3 at the end of messages, until the company put a stop to it for a now unknown reason. DoCoMo officially brought back a new version of the heart in 1999, along with 175 more icons, and voilà —emoji!
Emoticons are differentiated from emojis in that they are markings of facial emotions. In some instances, there has been a greater breath of protection for emoticons because emojis can often be found to be non-distinctive images of basic things or public domain symbols. There is a high threshold to find distinctiveness in either marking and depending upon where you attempt to register these symbols the outcome will vary. In the United States, the USPTO has been more flexible about finding an adequate level of distinctiveness, but in the EU the success rate of registration has been low.
The word "emoji" derives from the Japanese “e” (絵文字: 絵) which means picture, and “moji” (文字) which means character. Thanks to Fast Company's Co. Design for featuring a slew of interesting details about the design history of the original 176 emoji from a new book and accompanying keyboard app called 'Emoji,' published by Standards Manual in the fascinating article, "The Untold Design Story Of The Original Emoji."