The authors range widely, if not deeply, among the many facets of homosexuality--biological, cultural, political--to provide a sensible introductory handbook to the gay experience. Biologist LeVay (The Sexual Brain, 1993) and fiction-writing teacher Nonas, both of whom teach at LA's Institute of Gay and Lesbian Education, tackle virtually every question that would occur to someone curious about homosexuality. Beginning with an elementary but welcome definition of terms, the authors briefly survey homosexuality in several cultures and ages, highlighting the vast variety of ways gays and lesbians can express their sexuality. The book covers the biological research by LeVay himself, among others, on possible anatomical differences between the brains of gay and straight people, and presents an evenhanded discussion of opposition theories as well. Analyzing demographics, the authors suggest persuasively that gays and lesbians number only two to five percent of the population (which will annoy ""one-in-ten"" activists). With chapters on ethnic and disabled minorities, localities with large gay populations, and religious and sexual diversity, the authors remind us that gays and lesbians are a community only by virtue of their common sense of difference. The book floats off track with a longish account of New Age goofiness on lesbian communes and scattershot chapters on gay and lesbian art; a sensitive consideration of AIDS and great nonpartisan overviews of gay progress in civil rights and politics make up for the lapses. Generally the authors keep the discourse simple and perky, even when discussing sadomasochism and pedophilia; though this can be unsettling, the absence of polemics is refreshing. From Sappho to sodomy laws, Levay and Nonas hit all the resonant points of gay life and culture--but on a primer level that will offer most to those who know least about homosexuality.