Date, Designation & Address of the Recipient of a letter is called -

There are six parts in a formal/ official letter -
1. Heading: Date, Designation (পদবী) & Address of the Recipient
2. Salutation (সম্বোধন) : যেমন - Dear Sir/ Madam
3. Body (মূল বক্তব্য)
4. The Subscription: যেমন - Yours faithfully/ I remain, Sir
5. Signature of the Writer
6. Superscription: Detailed Designation & Address on the Envelope