In e-mail context, bcc stands for "blind carbon copy." When sending an email, the "To" field is where you put the primary recipients, while the "Cc" (carbon copy) field is where you put the secondary recipients who are being copied on the message. The "Bcc" (blind carbon copy) field is used for recipients who should receive the message, but whose identities should be kept hidden from other recipients in the "To" and "Cc" fields. This is commonly used when sending an email to a large group of people where you want to protect the privacy of everyone's email address.