Again is an entertainment system by AsiaTech Interplanetary, a corporation of the United Earth Federation. Again is arguably the most popular human invention and without any doubt one of the most controversial. The idea of Again was first thought up by Professor Trent Mi of Universitas mere years after time travel was successfully practiced. Today, Again allows users to seemingly travel back to any point in time and experience life in that time as an actual person of the time.
Contrary to popular belief, users of Again do not, in any way, travel back in time. When buying Again, users receive an enclosed chair which looks like an egg when closed, wherein users need to sit and allow the machine to "integrate" with the person in some respects. Once users are asleep, the "menu" of Again appears in their new state of consciousness (which is not normal sleep, imagination, or dreaming, but an induced ultra-realistic program which has been downloaded into the user's brain), where they decide to which point in time they want to travel.
Using actual time travel technology, the point to which users travel is indeed an exact replica of that time. If the user does not involve themselves with the new timeline, events would happen as they did in actual history, in every aspect. However, once a user becomes involved, "ripples" start to move throughout the time (their new state of consciousness), which changes events based on how big the user's contribution to new history is.
The process is an exact replica of actual time travel, however, indeed only a replica. In actual time travel, the balance of time can be damaged which can, and has almost at times, caused severe casualties numbering in the billions. However, Again "copies" actual time travel and allows users to do whatever they wish, whenever they wish, with the option of returning to the "Current Actual Time" (CAT). Users can save timelines in which they partake, which are known as "Alternative Time" (AT), and return to them at any time to resume them from the exact moment they left the timeline.
Again, especially among conservative humans, has attracted unprecedented amounts of controversy. AsiaTech has, since the invention of the first version of Again in 3156, paid over 100,000,000 trillion in damages caused by Again.
The now-medical condition SIT Syndrome (Stuck In Time Syndrome) is when users become either obsessed/addicted to their Alternative Time, can no longer distinguish between AT and CAT, or have been so confused by their AT that nothing in the CAT makes sense to them. Some people have, in fact, been literally stuck within their AT, however, those were glitches in the system which have been since fixed. An estimated 3 billion people have been diagnosed with SIT Syndrome between 3280 and 3300. SIT Syndrome can only be cured through excessive psychology, however, this has also been proven to be high ineffective, as users seek psychological help from "persons" in their Alternative Time as well, further confusing them and widening the gap between their AT and CAT.
As has been said, users are able to do anything humanly possible within their Alternative Time, and record it. This has led to widespread outrage throughout the galaxy, among humans and other species. Billions of recordings annually show heinous activities, such as killing sprees and torture of the "native" AT population. AsiaTech has since at numerous times stated that the population in the AT is an exact recreation, and not an actual individual.
Some species have begun prosecuting users for what they have done within their AT, however, AsiaTech has made it impossible for any government or institution to view doings within an AT without the user explicitly choosing to record their doings. The company has also stated that it would not limit users' freedom within their ATs, as that would "defeat the entire purpose Again."