From Learning Japanese Wiki (RtKWiki)
These are popular acronyms that are commonly used on the Reviewing the Kanji forums.
- AAP: All About Particles 
- AJATT: All Japanese All the Time 
- BJT: Business Japanese Proficiency Test (ビジネス日本語能力テスト) 
- C2k, C6k - Refers to the Core 2000 and Core 6000 sentences from iKnow/smart.fm, approximately 6000 total sentences with native audio and translations that have been made into shared Anki decks.
- DOJG: Also DOBJG, DOIJG, DOAJG. Refers to the 3 volumes (Basic, Intermediate, Advanced) of the Dictionary of Japanese Grammar series, by Makino & Tsutsui.
- EJV: Essential Japanese Verbs 
- JBiz: Alternate name for BJT
- JMW: Japanese the Manga Way
- JLPT: Japanese Language Proficiency Test (日本語能力試験) 
- JSPfEC: Japanese Sentence Patterns for Effective Communication
- KanKen: Japanese Kanji Aptitude Test (日本漢字能力検定試験) 
- KiC: Kanji in Context 
- KM: Kanzen Master 
- KO2001: Kanji Odyssey 2001 
- L1, L2, etc.: Used to refer to a learner's first, or native language(s), and their second, or target language (e.g. L1 = English, L2 = Japanese, for a native English speaker learning Japanese).
- RevTK: Reviewing the Kanji 
- RTH: Remembering the Hanzi
- RTK: Remembering the Kanji
- RTK1: Remembering the Kanji 1: A Complete Course on How Not to Forget the Meaning and Writing of Japanese Characters
- RTK2: Remembering the Kanji 2: A Systematic Guide to Reading Japanese Characters
- RTK3: Remembering the Kanji 3: Writing and Reading Japanese Characters for Upper-Level Proficiency
- SRS: Spaced Repetition System/Software 
- TTS: Text-to-speech
- UBJG: Understanding Basic Japanese Grammar