Where is documentation for CJK input methods (Its)? How the Chinese Pinyin IM &amp; Japanese Kana IM work is obvious (at least to me) but I have been experimenting unsuccessfully for a while with one of the Korean ones.  Keyboard viewer helps, but using it is proctalgia (at least for me).  Plus, understanding how it works is probably much easier than memorizing several dozen keystroke sequences.

Trying to find documentation by web search (with "Mac" or "OS X" in the search input) gives me:


Many hits for Windows and Linux
Many hits for how to select the IM
One hit for System 8.5
One page about a free KoreanIM "from Apple" (NOT!) that is actually malware.


Are any of the CJK input methods documented anywhere in English or Spanish?
Years ago (for OS 9 I think) Apple produced manuals for these IM's, which you can sometimes still find online, but I don't know how useful they are now.

For OS X, for each IM, when it is active, you should find a Help item further down in the "Flag" menu.  Below is what comes up for Korean.  Otherwise you have to rely on google to find explanations provided by individuals, such as

http://www.koreanfromzero.com/install_korean/mac_osx/ 

for the 2-Set IM.  Below are also cheat sheets for the two Romaja IM's I found (first Gongjincheong and then HNC).