A Secret Santa is someone who sends you gift(s) anonymously, then eventually reveals their name to you. There are various ways you can 'play'. Often, you draw names in a church/school/work group and then purchase or make small gifts over the course of several weeks before the holiday, or sometimes over the course of a year. You leave the gift somewhere where the recipient will find it, or mail it with no return address to preserve the mystery. Typically, the gifts are very small in value. At the end, you reveal your name, often at a holiday party.