First Day Covers are issued on the first day of availability of new set of postage stamps. They are cancelled with Official Postmark meant for that day. Usually philatelists are collecting these FDCs for their collection. However, some philatelists try to commercially use these Official or Private FDCs with appropriate postage using the same new stamps and get them cancelled with that  first day official cancellation postmark. Such first day commercial use of new stamps give a special dimension to these covers.

Here an effort is made to present such first day commercially used covers.