A "Beard" is a term used in gay communities which refers to the female companionship that a gay or gay-leaning bisexual male wears in his life to disguise the face of his true preference for the companionship of other males. Gays and gay-leaning bisexuals have been known to take on a beard as young as 13 years old, from studies of suicide notes of teens who committed suicide due to concerns over their (homo/bi) sexuality.
The use of beards has long been a favorite strategy of Hollywood agents and publicists, often recommended to, or imposed upon, a male celebrity, and sometimes the beard is even paid a lump sum or a salary to play the desired role. In the past, the "beard" strategy has often been combined with leaked stories/pictures to selected reporters regarding liaisons between gay celebrities and females (beards or otherwise), which often then showed up in various rags, and in the modern-day these strategies are sometimes combined with paying Internet surfers for their opinions to combat fans who say their favorite celebrity is gay/bisexual.
And taking it even further, upon the recommendation of agents and publicists, some gay or gay-leaning bisexual celebrities even pick up hookers and/or hire call girls, and pay them primarily to spread stories about their (heterosexual) prowess throughout the community.
However, there are always people in a celebrity's life who know the truth, and that truth often bubbles to the surface, either from the celebrity's own community, or the community of friends which the celebrity frequents.
And when all else fails, and when a young gay actor refuses to play ball and remain closeted, then there is always the old "nude pictures" trick, where someone gets the young actor into a position where allegedly unflattering nude pictures can be taken of him, and then those pictures are used as blackmail for the entire career of the young actor, forcing the young actor to play ball and remain closeted, whether he likes it or not.
The agents, publicists, celebrities, etc., who do these things are not necessarily bad people, often they simply don't understand that their efforts are contributing to the disproportionate numbers of gay/bi teen suicides, and many of them simply do what they are doing for money, or for recognition. Check out the Human Rights Campaign web site to begin to understand the impact of such choices on gay/bi teens.
And the reason why Hollywood tries so hard to hide the truth about the sexual preferences of so many of their actors is found in this article: Where Have You Gone, Rock Hudson?