Ever since the highly anticipated first episode of Serial season two premiered on Dec. 10, the internet has not stopped talking about it. Season 2 follows the story of Sgt. Bowe Bergdahl, the U.S. solider who walked away from his post in Afghanistan in 2009, was captured by the Taliban, released in 2014, and now faces court-martial for desertion. Yet it seems Serial will not focus as much on his capture or release as on Bergdahl's claim that he didn't desert: That he was merely hoping to initiate a DUSTWUN in order to bring attention to "failed leadership." But what does DUSTWUN mean? And what is the difference between that and the better known military acronyms AWOL, POW, and MIA?

According to Serial and Abbreviations.com, DUSTWUN is a military acronym meaning "duty status - whereabouts unknown." Pronounced "dust-one," it means that the person cannot be located, but it's not clear why (i.e. if he/she is missing, has deserted, or is being held captive). By default, this implies that this is a first-level classification while AWOL, someone who is "absent without official leave;" POW, "prisoner of war"; and MIA, "missing in action" are classification used after ones whereabouts/reasons for departure are known. So at what point does someone go from DUSTWUN to AWOL, POW, or MIA? Is it time-sensitive or intel-specific? Who or what makes the call?

Serial hasn't explained that yet, but it seems that both time and what is/is not known play a part. The important thing to know, according to Sarah Koenig, the host of Serial, is that DUSTWUN is "the Army's version of "man overboard," as she put it in the first episode of the new season, and Bergdahl claims he was specifically seeking this status. As Koenig summarized his take on his motives:

Bowe says what he was trying to do was to cause a DUSTWUN, which already sets him apart, because it means Bowe doesn't fit into any of the AWOL or desertion scenarios we're used to hearing. He wasn't cavorting. He wasn't drunk or goofing off. He didn't drop his weapon and flee in the middle of a firefight. He didn't decide in a burst of panic or confusion to go walk about.

Bergdahl reportedly knew that a DUSTWUN would make waves all the way up the chain of command. He claims his thinking was that it would lead to an investigation of his unit, which would ultimately bring to light the incompetence of that unit's leadership. If Bergdahl is telling the truth, he sought out DUSTWUN status because it was different from AWOL (and since he didn't disappear in combat, he wouldn't be MIA). The blame would fall on his command first.

And sure enough, when Berdahl disappeared, the DUSTWUN reportedly went all the way up to the central command in Afghanistan. We can't know whether Bergdahl's account of what led to his DUSTWUN is true, but then again, that's likely why Serial is investigating it in season two. Hopefully Sarah Koenig will answer that question in due course. In the meantime, you've learned another acronym.

Image: U.S. Army/Getty Images News