First of all, unlike most Western countries, in Japan you are not free to choose any name you want. There is a list of 2232 approved kanji for names. If the kanji you chose for your child is not on that list, it’s not allowed, and the birth registration will be denied! This made news a few years ago when a couple tried to name their child “akuma”, or demon. As you might expect, this didn’t go down too well at city hall (although the name was mistakenly accepted once), and they took the battle all the way to the courts. Eventually, though, they withdrew and renamed the child, which seems sensible…
In addition, the “v” sound, which sort of kind of exists in Japanese (it’s a katakana “u” with two dots) is only allowed when one of the two parents of the child is foreign. This is probably because it’s quite a hard sound for most Japanese to pronounce.
Another aspect of Japanese names is that middle names are not allowed. In the case of our teacher, the baby was given both a Japanese name and a Western name (Joshua Haruto), with the Japanese name “Haruto” being considered the middle name. However, for official registration purposes, his first name must be JoshuaHaruto.
While almost all Japanese names use kanji, a few women’s first names are written in hiragana only. However, it is extremely rare for a man’s first name to be hiragana only, possibly because hiragana is not seen as being a very masculine script.
As in many countries, male lineage is considered important, and when marrying, most women take their husband’s family name. However, in cases where the wife is the last of her family line (i.e., the only chance for future generations of that family), the man may take his wife’s family name so that the family line does not end. Double-barrelled names are never used.
Finally, another interesting if morbid aspect of Japanese names is that many people have a separate name that is only used after they have passed away, their “kaimyou”. This name will be inscribed on their tombstone, or more commonly, their urn. People can choose this for themselves, or often have a Buddhist priest choose it for them. For most people, this is similar to writing a will, in that they don’t think about it until it’s necessary. The new name usually has one kanji from their old name included in it, but otherwise can be entirely unconnected, and often is not even a standard name at all. However, in normal usage, even after a person has died, their friends and relatives will refer to them by their original name.
Some of the information for this article was taken from Wikipedia, which has an excellent article on the subject, for those interested in further reading.