Rokuyō (days of the week)
The rokuyō (六曜) are a series of six days that predict whether there will be good or bad fortune during that day. The rokuyō are still commonly found on Japanese calendars today, and are often used to plan weddings and funerals. The rokuyō are also known as the rokki (六輝). In order, they are:
先勝 (senshō) - Good luck before noon, bad luck after noon
友引 (tomobiki) - Bad things will happen to your friends. Funerals avoided on this day.
先負 (senbu) - Bad luck before noon, good luck after noon
仏滅 (butsumetsu) - Most unlucky day. Weddings best avoided.
大安 (taian) - Most lucky day. Good day for weddings.
赤口 (shakkō) - The hour of the horse (11 am - 1 pm) is lucky. The rest is bad luck.
Traditional month names
The name of month: (pronunciation, literal meaning)
January - 睦月 (mu tsuki)
February - 如月 or 衣更着 (kisaragi)
March - 弥生 (yayoi)
April - 卯月 (uzuki)
May - 皐月 or 早月 or 五月(satsuki)
June - 水無月 (mina tsuki or mina zuki, no water month)
July - 文月 (fumi zuki, book month)
August - 葉月 (ha zuki, leaf month)
September - 長月 (naga tsuki, long month)
October - 神無月 (kan'na zuki or kamina zuki, no god month), 神有月 (kamiari zuki, god month) only in Izumo province
November - 霜月 (shimo tsuki, frost month)
December - 師走 (shiwasu, teachers run; it is named so because even teachers are busy at the end of a year.)
Japanese era name
Japanese era name (年号, nengō, lit. year name) is a common calendar scheme used in Japan to count years. For example, 2004 is Heisei 16 years.
Like similar systems in East Asia, the era name system was originally derived from Chinese Imperial practice, although the Japanese system is independent from the Chinese or Korean calendar systems. Unlike other similar systems, the Japanese era name is still in use. Government offices usually require era names and years for official papers.

Sometimes an era name is expressed with the first letter of the romanized name. For example, S55 means Showa 55 years. With 64 years, Showa is the longest era.

Modern era names
With the modernization of Japan after the ascension of the Meiji Emperor and now under current Japanese law since 1979, it has become practice to change era names only upon occasion of imperial succession. Also, the deceased emperor will thereafter be referred to as his corresponding era name posthumously. Under current law, only males can assume the throne.
In the Japanese language, the current emperor on the throne is almost always referred to as Tennō Heika (天皇陛下, His Majesty the Emperor) or rarely and less formally as Kinjō Tennō (今上天皇, current emperor) and even more rarely, if ever by his name Akihito. To call the current emperor by the current era name Heisei even in English would be a faux pas as it is and will be his posthumous name. This causes great confusion not only in other languages, but also for Japanese as he is known throughout the world only as Akihito. Also, his father the 124th emperor is called Hirohito throughout the world, but is always called the Showa Emperor in Japan.

In modern practice, the first year of a reign (元年 gannen) starts immediately upon the emperor's ascension to the throne, but always ends on December 31st. Subsequent years follow the Western calendar. Consequently, 1989 is known as both "Showa 64" and "Heisei 1", although technically Showa 64 ended on January 7th with Hirohito's death.

Historic era names
Historically however, prior to the Meiji Restoration, era names were changed on many different occasions such as celebration, major political incidents, natural disasters, and so on, but the emperors posthumous name never took the name of an era. Incidentally, on modern official papers, those who were born prior to the Meiji era did not write the era name in which they born, but wrote Edo period (though now no one born over 130 years ago in that time period is still alive now).
Conversion table from eras to Gregorian calendar years
645 大化 Taika
650 白雉 Hakuchi
654 (Discontinued)
672 白鳳 Hakuhō
686 朱鳥 Shuchō
686 (Discontinued)
701 大宝 Daihō or Taihō
704 慶雲 Keiun
708 和銅 Wadō
715 霊亀 Reiki
717 養老 Yōrō
724 神亀 Jinki
729 天平 Tempyō
749 天平感宝 Tempyō-kampō
749 天平勝宝 Tempyō-shōhō
757 天平宝字 Tempyō-hōji
765 天平神護 Tempyō-jingo
767 神護景雲 Jingo-keiun
770 宝亀 Hōki
781 天応 Ten'ō
782 延暦 Enryaku
806 大同 Daidō
810 弘仁 Kōnin
824 天長 Tenchō
834 承和 Jōwa or Shōwa
848 嘉祥 Kajō
851 仁寿 Ninju
854 斉衡 Saikō
857 天安 Tennan
859 貞観 Jōgan
877 元慶 Genkei or Gangyō
885 仁和 Ninna
889 寛平 Kanpyō
898 昌泰 Shōtai
901 延喜 Engi
923 延長 Enchō
931 承平 Jōhei or Shōhei
938 天慶 Tengyō
947 天暦 Tenryaku
957 天徳 Tentoku
961 応和 Ōwa
964 康保 Kōhō
968 安和 Anna
970 天禄 Tenroku
973 天延 Ten'en
976 貞元 Jōgen
978 天元 Tengen
983 永観 Eikan
985 寛和 Kanna
987 永延 Eien
988 永祚 Eiso
990 正暦 Shōryaku
995 長徳 Chōtoku
999 長保 Chōhō
1004 寛弘 Kankō
1012 長和 Chōwa
1017 寛仁 Kannin
1021 治安 Jian
1024 万寿 Manju
1028 長元 Chōgen
1037 長暦 Chōryaku
1040 長久 Chōkyū
1044 寛徳 Kantoku
1046 永承 Eishō or Eijō
1053 天喜 Tengi
1058 康平 Kōhei
1065 治暦 Jiryaku
1069 延久 Enkyū
1074 承保 Jōhō
1077 承暦 Shōryaku or Jōryaku
1081 永保 Eihō
1084 応徳 Ōtoku
1087 寛治 Kanji
1094 嘉保 Kahō
1096 永長 Eichō
1097 承徳 Jōtoku
1099 康和 Kōwa
1104 長治 Chōji
1106 嘉承 Kajō
1108 天仁 Tennin
1110 天永 Ten'ei
1113 永久 Eikyū
1118 元永 Gen'ei
1120 保安 Hōan
1124 天治 Tenji
1126 大治 Daiji
1131 天承 Tenshō or Tenjō
1132 長承 Chōshō or Chōjō
1135 保延 Hōen
1141 永治 Eiji
1142 康治 Kōji
1144 天養 Ten'yō
1145 久安 Kyūan
1151 仁平 Nimpei or Nimpyō
1154 久寿 Kyūju
1156 保元 Hōgen
1159 平治 Heiji
1160 永暦 Eiryaku
1161 応保 Ōhō
1163 長寛 Chōkan
1165 永万 Eiman
1166 仁安 Ninnan
1169 嘉応 Kaō
1171 承安 Shōan or Jōan
1175 安元 Angen
1177 治承 Jishō or Jijō
1181 養和 Yōwa
1182 寿永 Juei
1184 元暦 Genryaku
1185 文治 Bunji
1190 建久 Kenkyū
1199 正治 Shōji
1201 建仁 Kennin
1204 元久 Genkyū
1206 建永 Ken'ei
1207 承元 Jōgen
1211 建暦 Kenryaku
1213 建保 Kempō
1219 承久 Jōkyū
1222 貞応 Jōō
1224 元仁 Gennin
1225 嘉禄 Karoku
1227 安貞 Antei
1229 寛喜 Kanki or Kangi
1232 貞永 Jōei
1233 天福 Tenpuku
1234 文暦 Bunryaku
1235 嘉禎 Katei
1238 暦仁 Ryakunin
1239 延応 En'ō
1240 仁治 Ninji
1243 寛元 Kangen
1247 宝治 Hōji
1249 建長 Kenchō
1256 康元 Kōgen
1257 正嘉 Shōka
1259 正元 Shōgen
1260 文応 Bun'ō
1261 弘長 Kōcho
1264 文永 Bun'ei
1275 建治 Kenji
1278 弘安 Kōan
1288 正応 Shōō
1293 永仁 Einin
1299 正安 Shōan
1302 乾元 Kengen
1303 嘉元 Kagen
1306 徳治 Tokuji
1308 延慶 Enkyō or Enkei
1311 応長 Ōchō
1312 正和 Shōwa
1317 文保 Bunpō
1319 元応 Gen'ō
1321 元亨 Genkyō or Genkō
1324 正中 Shōchū
1326 嘉暦 Karyaku
1329 元徳 Gentoku
1331 元弘 Genkō
1334 建武 Kemmu
1336 延元 Engen
1340 興国 Kōkoku
1346 正平 Shōhei
1370 建徳 Kentoku
1372 文中 Bunchū
1375 天授 Tenju
1381 弘和 Kōwa
1384 元中 Genchū
1390 明徳 Meitoku
1394 応永 Ōei
1428 正長 Shōchō
1429 永享 Eikyō
1441 嘉吉 Kakitsu
1444 文安 Bunnan
1449 宝徳 Hōtoku
1452 享徳 Kyōtoku
1455 康正 Kōshō
1457 長禄 Chōroku
1460 寛正 Kanshō
1466 文正 Bunshō
1467 応仁 Ōnin
1469 文明 Bunmei
1487 長享 Chōkyō
1489 延徳 Entoku
1492 明応 Meiō
1501 文亀 Bunki
1504 永正 Eishō
1521 大永 Daiei
1528 享禄 Kyōroku
1532 天文 Tembun or Temmon
1555 弘治 Kōji
1558 永禄 Eiroku
1570 元亀 Genki
1573 天正 Tenshō - the name was suggested by Oda Nobunaga
1592 文禄 Bunroku
1596 慶長 Keichō
1615 元和 Genna
1624 寛永 Kan'ei
1644 正保 Shōhō
1648 慶安 Keian
1652 承応 Jōō
1655 明暦 Meireki
1658 万治 Manji
1661 寛文 Kambun
1673 延宝 Empō
1681 天和 Tenna
1684 貞享 Jōkyō
1688 元禄 Genroku
1704 宝永 Hōei
1711 正徳 Shōtoku
1716 享保 Kyōhō
1736 元文 Gembun
1741 寛保 Kampō
1744 延享 Enkyō
1748 寛延 Kan'en
1751 宝暦 Hōreki
1764 明和 Meiwa
1772 安永 An'ei
1781 天明 Tenmei
1789 寛政 Kansei
1801 享和 Kyōwa
1804 文化 Bunka
1818 文政 Bunsei
1830 天保 Tempō
1844 弘化 Kōka
1848 嘉永 Kaei
1854 安政 Ansei
1860 万延 Man'en
1861 文久 Bunkyū
1864 元治 Genji
1865 慶応 Keiō
1868 明治 Meiji - Mutsuhito, the Meiji Emperor
1912 大正 Taishō - Yoshihito, the Taisho Emperor
1926 昭和 Shōwa - Hirohito, the Showa emperor
1989 平成 Heisei - Akihito, the reigning emperor
#-s Dài quá! Mà ko biết có chưa nữa. :frown:
http://www.jref.com/culture/japanese_traditional_calendar.shtml