ddd had been indicated as DDD from its establishment in 1991 until 2004, but this database has adopted the unified notation ddd.
- The chronology in this site is a reference material for the ddd DATABASE.
- The chronology compiles information on the following 12 contents: "ddd Events," "World Events," "Graphic Design‘s Events," "JAGDA New Designer Award," "ADC Grand Prix," "TDC Grand Prix," "Media," "Culture," "Japanese Buzzword Award," "Word of the Year," "Hit Items," and "Pop Music. "
- Some of the events, product names, company names, etc., listed in each category are described by commonly known names, and some are not official names.
- The "Word of the Year" with (ADS) at the end is published by the American Dialect Society, and ones with (Oxford) at the end is published by Oxford Languages. Oxford Languages' Word of the Year has been listed since 2004.
- For sources and references for the information listed in each item, please refer to "Sources/References" below.
- The English indication of "JAGDA New Designer Award," "ADC Grand Prix," and "TDC Grand Prix" are based on the official announcements made by the organizing bodies of the awards.
- Miho Takagi was in charge of "ddd Events." The other 11 contents were collected and edited by Sakura Nomiyama. All the contents agreed upon by the planning team of the ddd DATABASE are published in the chronology.
- Seisou Fuzoku Observatory,Heisei Seisou Fuzoku Shishi Nenpyo, Kawade Shobo Shinsha, 2019.
- JIJI.COM, "[Illustration] What happened that year? The 10 Greatest News of the Heisei Era (1989-2018)"
- The Yomiuri Shimbun Online, "The 10 Greatest News as Selected by Readers"
Graphic Design’s Events
- Idea, No. 369, Seibundo Shinkosha, 2014.
- Resonance of Vision: Katsui Mitsuo, Mitsuo Katsui, Mitsumura Book Publishing, 2019.
- MdN, April 2019, Vol. 298, MdN Corporation, 2019.
- AXIS, Vol. 213, Axis, 2021.
JAGDA New Designer Award
ADC Grand Prix
- Tokyo Art Directors Club, ADC Yearbook, Bijutsu Shuppansha, 1991-2021.
TDC Grand Prix
- Reiko Tsuchiya,Chronological Table of Japanese Media History, Yoshikawa Kobunkan, 2017.
- Barubora, Sayawaka,Bokutachi no Internet Shi (Our Internet History), Aki Shobo, 2017.
- NHK, "Heisei Net History (Tentative)" Reporting Team, Heisei Net History: Eternal Beta Version, Gentosha, 2021.
- Sesou Fuzoku Observatory,Heisei Sesou Fuzoku Shishi Nenpyo, Kawade Shobo Shinsha, 2019.
Japanese Buzzword Award
Word of the Year
- Nikkei Trendy,Nikkei Trendy '90s Hit Products: A Comprehensive Review, Nikkei Home Publishing, 1998.
- Nikkei Trendy,30 Years 1987-2016 Strongest Hit Product Ranking : The Complete Preservation Edition, Nikkei BP, 2018.
- Nikkei Cross Trend, "The 30 best hit products in 2021,"
- Nikkei Cross Trend, "The 30 best hit products in 2020,"
- Nikkei Cross Trend, "30 Best Hits in 2019,"
- Nikkei Cross Trend, "30 Best Hits in 2018"
- Nikkei Cross Trend, "30 Best Hits of 2017"