Buffy the Vampire Slayer comics refer to comic books based on the television series Buffy the Vampire Slayer. While many of these comics were published when the television show was on air they are not all considered canonical and often deal with characters who do not appear on in the television series, most notably in the Tales of the Slayers and Tales of the Vampires mini-series.
The books were published by Dark Horse Comics between 1998 and 2004, originally in comic format but then gathered into volumes of trade paperbacks. A small number of Buffy comics have not been included in trade paperbacks, such as the books entitled "Giles", "Jonathan", and "Reunion".
Despite not all comics being canonical, series creator Joss Whedon and a number of writers involved with the television series authored many of the comic books. Overviews summarizing the comic books' storylines were written early in the writing process and were 'approved' by both Fox and Joss Whedon (or his office), and the books were therefore later published as official Buffy merchandise.
The stories in the Buffy comics take place in between episodes of the Buffy the Vampire Slayer TV series, and continue after the series ended. Issues 1 to 63 take place during the period that the series was still on air, and none are written by Joss Whedon himself. The earlier issues are not very easy to place in the series other than the season they are set in. The stories get more specific later on, however; for example, the Oz Buffy comics fill in the story line of Oz's character after he leaves the TV series, and the Death of Buffy comics clearly take place between Seasons 5 and 6 of the series.
Starting in 2007, a new series of Buffy comics has been produced, also published by Dark Horse Comics. These are a canonical continuation of the television series and as such are considered Buffy the Vampire Slayer Season Eight. One of the other comics considered canon is the 8-part series Fray, since the main character, Melaka Fray, appears in Season 8. Buffy the Vampire Slayer Season Eight takes place after the series ended, and the issues are written by Joss Whedon to continue the storyline.