- Contents -
  Q What is a personal computer?
  Q How do personal computers output Kanji?
  Q What is a font?
  Q What is a character code?
  Q How are Kanji input?
  Q Is it impossible to use characters not in the character set?
  Q Do I only need a user-defined character editor to use user-defined characters?
  Q How do I input user-defined characters with IME?
  Q Is it possible to use characters from mainframes?
  Q What is the JIS code?
  Q What is the Shift JIS code?
  Q What is Unicode?
  Q How long will it take for Unicode to become available?
  Q What is XKP?
  Q Can user-defined characters be transferred using XKP?
  Q Is it possible to use more user-defined characters than the number of character codes available?
  Q Can XKP user-defined characters be printed?

Japanese Processing Guidebook


Q Is it impossible to use characters not in the character set?

A It is possible to use them, but there are several problems involved.

PCs usually possess a user-defined character function.
This function allows the user to record particular characters that they want to use, and handle them just as if they were registered as standard characters.
These are called user-defined characters.
This is a very convenient function, and allows you to use characters that do not have a character code by recording those you wish to use, thus making it possible to use any character at all.
However, user-defined characters currently have the following problems.

- The number of characters available may be too few.
For example, the standard number of user-defined characters available under Windows is 1880 characters. However, this may be insufficient when recording information such as large numbers of individuals' names.

- Data transfer is impossible.
User-defined characters are basically meant to be recorded on one PC, and can only be used on that PC. However, these days it is normal for PCs to be connected together via LANs, the Internet and other data communication methods. If a document using user-defined characters is transferred over a network, the necessary characters are not recorded on the PC on the receiving end, resulting in those characters not being displayed. For this reason, it is considered good manners not to use user-defined characters when sending electronic mail or other digital information.
Of course, even if the data is transferred between PCs by floppy disk, the same phenomenon occurs.

There are two ways of dealing with these problems.
One is to make a character set that includes more characters and use that instead. At the moment, new JIS standards - the third and fourth JIS standards and JIS X 0213 - are in the process of being defined, but they have not yet reached a usable level.
The other way is to create a safer process for handling user-defined characters. This includes XKP (Windows NT eXtended Kanji Processing).