[Definition] Dorama

Japanese television drama (テレビドラマ terebi dorama^?, television drama), also called dorama (ドラマ^?), are a staple of Japanese television and are broadcast daily. All major TV networks in Japan produce a variety of drama series including romance, comedy, detective stories, horror, and many others. For special occasions, there may also be a one- or two-episode drama with a specific theme, such as a drama produced in 2007 for the 60-year anniversary of the end of World War II.

Japanese drama series are broadcast in three-month seasons, with new dramas airing each season. The majority of dramas are aired week-days in the evenings around 9:00 p.m., 10:00 p.m., or even 11:00 p.m. Dramas shown in the morning or afternoon are generally broadcast on a daily basis, and episodes of the same drama can be aired every day for several months, such as NHK's asadora, or morning dramas. The evening dramas, however, air weekly and are usually nine to twelve episodes long, though sometimes there will be an epilogue special made after the final episode if the drama has been a huge success.
Japan has four television seasons: Winter (January–March), Spring (April–June), Summer (July–September), and Autumn or Fall (October–December). Some series may start in another month though it may still be counted as a series of a specific season.
One characteristic of Japanese drama that differentiates it is that each episode is usually shot only a few (two to three) weeks before it is actually aired. Many fans have been able to visit their idols shooting scenes even as the show is still airing.

source: wikipedia.org