What Does the Red Equals Sign on Facebook Mean?

Perhaps you've seen this red equals sign appear on your Facebook feed.  What does it signify?

The symbol shows support for marriage equality.  The United States Supreme Court is hearing oral arguments this week on two cases involving gay marriage.

The first case, argued on Tuesday involved California's Prop 8.  The law banned same sex marriages in the state.  However, the state is currently not enforcing the law.

The second case, being heard on Wednesday, centers around the federal Defense of Marriage Act (DOMA) which was signed into law during the Clinton Administration.

DOMA, opponents argue, sets up separate classes of individuals since legal state-sanctioned same-sex marriages are not recognized by the federal government.

Decisions in both cases are expected this summer.