MENLO PARK, Calif. — Facebook's users don't have to describe themselves as just male or female anymore.
The social media giant has added a customizable option with about 50 different terms people can use to identify their gender.
They also now have three preferred pronoun choices for being addressed: him, her or them. (As in: "Wish them a happy birthday!")
Facebook said the changes, shared with the Associated Press before the launch on Thursday, initially cover the company's 159 million monthly users in the United States and are aimed at giving people more choices in how they describe themselves, such as androgynous, bi-gender, intersex, gender fluid or transsexual.
"There's going to be a lot of people for whom this is going to mean nothing, but for the few it does impact, it means the world," said Facebook software engineer Brielle Harrison, who worked on the project and is herself undergoing gender transformation, from male to female.
"All too often transgender people like myself and other gender nonconforming people are given this binary option, do you want to be male or female? What is your gender? And it's kind of disheartening because none of those let us tell others who we really are," she said.
Facebook, which has 1.23 billion active monthly users around the world, also allows them to keep their gender identity private and will continue to do so.
The Williams Institute, a think tank based at the University of California at Los Angeles, estimates there are at least 700,000 individuals in the United States who identify as transgender, an umbrella term that includes people who live as a gender different from the one assigned to them at birth.
But the high-profile development seemed senseless to those who believe in only two genders.
"Of course Facebook is entitled to manage its wildly popular site as it sees fit, but here is the bottom line: It's impossible to deny the biological reality that humanity is divided into two halves — male and female," said Jeff Johnston, an issues analyst for Focus on the Family, a national religious organization based in Colorado Springs, Colo.
The move by Facebook came after years of lobbying from users, including some who started Facebook pages to petition for the change. Google+ offers male, female and "other" as choices.
The idea of expanding gender choices percolated at Facebook for about a year and started to come to fruition during an in-house brainstorming four months ago, project manager Lexi Ross said.
"Really, there was no debate within Facebook about the social implications at all," said Alex Schultz, director of growth. "It was simple: Not allowing people to express something so fundamental is not really cool so we did something. Hopefully a more open and connected world will, by extension, make this a more understanding and tolerant world."