“The only way I will rest in peace is if one day transgender people aren’t treated the way I was, they’re treated like humans,” she wrote. “Fix society. Please.”

Three years before a police raid of the Stonewall Inn in New York in June 1969 galvanized the gay rights movement in America, transgender women rioted after being expelled from Compton’s Cafeteria in San Francisco. The restaurant had become one of the few safe gathering spots for the city’s community of transgender people, who at the time were not welcome at gay bars. That same year, physician Harry Benjamin published “The Transsexual Phenomenon,” a groundbreaking book that outlined how transgender people could transition medically. The two developments helped give rise to an arduous fight for societal acceptance.

Over the decades, the transgender movement has been part of the broader quest for equality for sexual minorities, but while gays and lesbians have achieved far-reaching legal and political victories in recent years, transgender people, who may be gay or straight, remain among the nation’s most marginalized citizens. They face distinct challenges, including access to transition-related medical care, which have not always been a focus of the broader struggle for gay rights. Gays and lesbians are visible in all walks of life today, and many are celebrities and role models. Transgender Americans, meanwhile, remained largely unseen until fairly recently.

As prominent transgender people have come out in recent years, their revelations have been a source of fascination, much of it prurient. There was the actress Laverne Cox, the Army whistle-blower Chelsea Manning and most recently, Bruce Jenner, the gold-medal Olympian. Their stories have brought attention to the plight of a segment of the population that continues to confound many Americans. One challenge lies in semantics, a complex and fraught subject given the extraordinary diversity of experiences within the transgender community. The term transgender covers a broad range of people who do not identify with the gender listed on their birth certificate.

Scientists have no conclusive explanation for what causes some people to feel dissonance between their gender identity and aspects of their anatomy. In 2013, the American Psychiatric Association updated its manual, replacing the term “gender identity disorder,” with one that is less stigmatizing, “gender dysphoria.”

The options for those who take steps to ease the distress has expanded significantly in recent years. Some opt to wear clothes typically associated with the sex they identify with, legally change their names and use new pronouns. Many also undergo hormone replacement therapy and have surgery to transform their bodies. Surgical procedures include chest reduction and augmentation as well as sex-reassignment surgery. Some people have just one type of procedure, others undergo both, and some choose to have none. While many transgender people identify with one gender, some feel their identity lies somewhere in between. The spectrum of experiences and identities is complicated, but taking basic steps to ensure that more transgender people lead healthy and fulfilling lives is not.