comics: "Juxtaposed pictorial and other images in deliberate sequence, intended to convey information and/or to produce an aesthetic response in the viewer," Scott McCloud in Understanding Comics, 1993.
sequential art: "A literary medium that narrates by arrangement of images and text in an intelligible sequence," Will Eisner in Comics and Sequential Art, 1985.
comic strip: Comics that appear daily in newspapers, usually three or four panels each; larger colorful versions appear in Sunday editions. (Garfield, Calvin and Hobbes)
comic book: Monthly paper issues of about 22 to 32 pages, often republished in collected volumes. (Ms. Marvel, Lumberjanes)
graphic novel: Longer form stories told in comic format, either as stand-alone books or series. (Drama, Amulet)
panel: One segment of the story or action; the individual box or frame.
gutter: The space between panels.
tier: One row of panels.
splash page: One page that consists entirely of one illustration.
spread: An image that spreads across multiple pages (a two-page spread is most common).
speech balloon: Contains a characters spoken dialogue with a pointer or tail to indicate the speaker.
thought bubble: Shows a character's unvoiced thoughts in a cloud shape, using bubbles as an indicator.
caption: A rectangular box which provides a narration, sometimes used for dialog when the character speaking is not pictured in the panel.
sound effects: Or onomatopoeia are words that mimic sound like "Pow!" or "Buzz."