THEY actually stands for "The Hierarchy Enslaving You". The Truth is that when it comes down to it, THEY has many, many other names, such as the Illuminati, the United States Government, and Wikiaa – quite possibly with the inclusion of You.
THEY has been used in everyday English conversation for centuries. It is oftentimes disguised simply as They so that organizations such as the Illuminati and the United States Government may freely discuss the future of themselves. THEY has become so commonly used in today's Society that we no longer realize what it actually means.