On a related note I once read about a legal name which could not be entered in most computer systems. The man was a refuge from China (?) whose last name was the single letter "O." This was, almost always, flagged as an invalid last name because because it was too short. He legally changed it to "Oh" and was quoted as feeling that he was betraying his ancestors.
Last year in college I had a colleague that had only a first name. I didn't enquiry further as to why, but anyway, I figure it must be a pain.
It is common in some parts of the world. My country has > 1000 ethnic groups, and many of us don't recognize the concept of surname the way Westerners do. Nowadays most of us who don't have surname either have multiple given names (I'm in this category), or new parents just add Western-style surname to their babies' names. I'm in my 30s, personally acquainted (ie. work colleague, former classmates, etc) with ~5 people who has one name.
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