First Day Cover (FDC)
FDCs are issued on the same day as the stamp. They are officially issued envelopes with attached commemorative postage stamps in accordance with the issue plan, specially marked with the date of the first day of issue and a picture on the left-hand side of the FDC, usually printed by digital printing or die stamping from flat plates. The FDC can be used in postal operations for the first 3 months after the date of issue.