What is contextual iterative immersion (Cii)?
For instance, if you see a new example sentence, it will never have more than 1 word in it that you don't know. The piece of new information might be a single new vocabulary word, or a new kanji, or a recently introduced grammatical construction.
There are two main benefits to this system of teaching. First, the study materials do not feel overwhelming. Second, content is reinforced. If there is only one new word in a sentence, for example, then that means you are reviewing every other word in that sentence. You start to feel like you are getting better naturally rather than through tiresome effort.