This is the online manual for Kanji Tree, an app which aims to take the chore out of learning to read and write Japanese kanji.
It was written by an old-school video games programmer, who moved to Tokyo and was frustrated by the ineffectiveness of available learning resources.
Japanese children start learning to read when they are very young, so they learn kanji for simple words to begin with. Unfortunately, kanji for simple words often contain kanji from more advanced words.
For example, 話 (talk, tale) is comprised of 言 (say) and 舌 (tongue).
But while 話 is taught in grade two, 舌 isn't taught until three years later!
This approach may be necessary for children learning their first language, but adults learning Japanese as a second language can take a far more efficient route. It clearly makes more sense to learn 言, then 舌, then 話. That way, the last one can be memorized as two meaningful components, instead of thirteen random squiggles.
This is the reason Kanji Tree was created; so foreigners can learn kanji in a "tree" order. Learning visually simple kanji first, then building upon existing knowledge to learn in the most efficient way possible.
The learning task is split into three parts, with each part focusing on a different area of the brain.
Firstly, the Recognition Game is used to train your visual cortex to recognize the shapes of the individual kanji.
Secondly, the Reading Game is used to expand your vocabulary; teaching you words which use the kanji you have learned to recognize.
Thirdly, the Writing Game is used to cement the knowledge you have learned into your long-term memory, in a way that reading alone will never do.