Girl Genius is the name of the collected early histories of Lady Agatha Heterodyne, from her last days living in Beetleburg to whenever the Transylvania Polygnostic University grant runs out for the Professors Foglio and their associates.
Put another way, Girl Genius is the Foglios' long-running gaslamp fantasy graphic novel, published by Airship Entertainment with nineteen volumes in print as of April 2021, a twentieth and twenty-first volume complete and available on the web, and a twenty-second volume in progress and also available on the web, with new pages coming out three days a week on http://www.girlgeniusonline.com. Starting with the fourteenth volume, Girl Genius is said to have entered Act 2 or The Second Journey of Agatha Heterodyne, with the volume numbers starting over from one. The first thirteen volumes are now known collectively as Act 1 or The First Journey of Agatha Heterodyne.
Girl Genius tells of the journeys of a young woman who discovers she not only has great hidden talents for Mad Science, but is the heir to both a heroic legacy... and an evil which nearly destroyed a world which runs on steam, aesthetics, and fabulous improbabilities.
The series started as a quarterly "dead-tree" print comic, with extras like paper cutout novelties on the inside covers, such as a coder/decoder wheel, gift tags and Christmas ornaments. The comic also included extra stories (called "omake" in other realms) such as "An Agatha Heterodyne 1 Minute Mystery" and the Jägershots.
In 2005, the Foglios decided to take what many saw as a risk and change to a webcomic format, updating three times a week, with trade paperback reprints of collected material published about once a year. Girl Genius 101 started reprinting the material in the print comics from page 1; the Girl Genius Advanced Class contained brand-new material posted simultaneously with the older pages.
The experiment was wildly successful; their official fan group on Yahoo! had message numbers climb exponentially for the three months after the launch. Sales became quite healthy, allowing them to create and sell proprietary items such as winged trilobite pins as well as the books and the remaining copies of the original comic issues.
Girl Genius, Volume VIII won the inaugural Hugo Award for "Best Graphic Story" at AnticipationSF on August 9, 2009.  Girl Genius continued to dominate this category (with Volume IX winning in 2010 and Volume X in 2011), until Phil Foglio removed the work from contention for 2012 for the 2011 win.
The Collections and Other Editions
Main article: List of Published Volumes
The collected material, both from the original dead-tree issues 1-13, and the subsequent web-published pages, are collected in trade paperback and limited hardback editions. There is also a black-and-white omnibus of the first three collected volumes, and various related publications, both physical and virtual.
Defining 'Girl Genius'
Phil: "Gaslamp fantasy" is a term that Kaja made up. She thought she was quoting something else... and actually coined a phrase. A lot of people claim that Girl Genius is steampunk...
Interviewer: Nnn, I wouldn't say that.
Phil: I wouldn't either for a variety of reasons, one of which is that we have no punks. But gaslamp fantasy is that kind of adventure... story pretty much unhampered by actual physical facts, or adheres to the physical facts that were known around the late 1800s....
Inspirations and Influences
Main article: Recommended Reading
Kaja: Well, we started doing Girl Genius the way it is with... everybody knows the term 'steampunk'... with that aesthetic... At that time I was going through all of Phil's old files and I was filing all of the old sketches, and I was coming across weird airships and cats in top hats with walking canes and all of this wonderful... Victoriana sci-fi stuff.... ...I love airships, I love mad science, I love the Victorian stuff and the clanky machines and all of that business... I've always loved Jules Verne and H.G. Wells.... I look back more at, like, H. Rider Haggard adventure novels....
- Jane Austen
- H. Rider Haggard
- Kenneth Robeson
- Jules Verne
- H.G. Wells
- Vaugn Bode
- Frank Kelly Freas
- Wendy & Richard Pini
- Charles Schultz
- Osamu Tezuka
- Tex Avery
- Chuck Jones
- Studio Ghibli