DefinitionThe term fan service (also written sometimes as fanservice) are scenes or images whose sole purpose is to "excite or titillate the viewer", primarily male viewers but fan service can also be done for female viewers as well. Fan service has come to primarily refer to the following example types:
- Scantily-clad females
- Cleavage shots
- Panty shots
- Suggestive poses
- Nude scenes (bath and shower primarily)
- Girls caught changing clothes
A third form of fan service could be a title that was done strictly for fans of a series. An example of this would be Ai Yori Aoshi ~Enishi~ Miyuki which is a 15-minute OAV episode done strictly for fans of Ai Yori Aoshi.
Origination of Fan Servicea/o 26 September 2003...
The term "fan service" goes back to the late 80's at minimum. However, Dirty Pair was done in 1985 and clearly had fan service in mind even if they didn't expressly use the term then. The term "Gainax Bounce" has been described as fan service since their title Top wo Nerae! came out in 1988 (1). Gainax's anime parody of their own rise called 1982 Otaku no Video and 1985 Otaku no Video refers to fan service (2).
The first use of "fan service" on Usenet as refering to its current meaning was in 1994 by Hitoshi Doi (3). The actual first use of the term "fan service" on Usenet was done in 1991 by Tonghyun Kim and has a different context (3).
By the time Gainax released Shin Seiki Evangelion in 1995, the term "fan service" was well known. This explains why on the previews for the next episode, Misato often called for more "service" or promised more "service".
If more information is learned, I'll post an update.
(1) Rob Kelk
(3) John C. Watson
Above information compiled by AstroNerdBoy.