The terms yuri and shoujoai are often used to refer to anime or manga series that portray romantic or sexual relationships between girls or women. The history of these terms are a little fuzzy, though. And while some people use these terms as if they have clear distinctions, or as if they are interchangeable, the truth is that both are somewhat fluid, forming a broad continuum of definition and understanding. In other words, what each term means has a lot to do with who is using the term - and what they think it means.
In 1971, Ito Bongaku, the editor of Barazoku a gay men's magazine - called lesbians in Japan "the lily tribe" - bara is Japanese for "rose" and yuri is Japanese for the lily. Hence, gay men were barazoku, or "rose tribe" while lesbians were yurizoku, the lily tribe. This name was taken by many hentai manga and doujinshi artists, who then named their lesbian characters "Yuri" or "Yuriko," that it became a kind of cliche' for the genre itself. For instance, one of the most common early pairings in hentai doujinshi were Kei and Yuri from Dirty Pair. At Yuricon, we believe that it is long past time to reclaim the term from hentai artists.
Here in the west, the term yuri is often, but not exclusively, used to represent explicit sexual relations between women. Shoujoai (Girls' Love) is a pretty new term, for all that it's a pretty old concept. The term shoujoai was created as an analog for shounenai (Boys' Love)...by an American fan. It isn't really used in Japan - although they know what we mean when we use it. Shoujoai is often used to refer to romantic love between girls - sometimes with sex, sometimes not. The emphasis tends to be on the romantic over the sexual, but this is a convention that was made up by Americans and has no meaning at all in Japan.
For five years, we at Yuricon have been working to define yuri as something more than just porn for men, since that definition ignores an entire body of truly excellent lesbian-themed works by and for girls and women - not to mention the non-pornographic works by men. To this end, we at Yuricon would like to offer this definition of yuri:
Yuri can be used to describe any anime or manga series (or other thing, i.e., fan fiction, film, etc.) that shows intense emotional connection, romantic love or physical desire between women. Yuri is not a genre confined by the gender or age of the audience, but by the *perception* of the audience. We can, if we want to, differentiate between shounen yuri - written by men for a primarily male audience; shoujo yuri - written by women for a primarily female audience and; what we at Yuricon like to think of as "pure" yuri - written by lesbians for a lesbian audience...but it's still all yuri.
In short, yuri is any story with women in love (or lust) with other women
