What does the TO at the beginning of the greeting card mean?

The sender means the sender.

To means in English: where to go?

From in English means: Where are you from?

The format of translation into Chinese is

Recipient = Recipient's first name

Sender = = sender's name

The origin of greeting cards

Emperor Taizong greeted the ministers with greeting cards. Every Spring Festival and Spring Festival, from the head of state to ordinary people, he has the habit of sending greeting cards to relatives and friends. When did the greeting card, a special blessing medium, come into being, why has it spread so far, and what kind of development and changes have it experienced?

China's traditional culture attaches great importance to "ceremony", which was once the essence of China culture. Many contents in etiquette are expressed through forms, such as greeting cards. Giving greeting cards before important personal activities or public holidays is solemn in form on the one hand, and convenient for both parties to inform each other in advance on the other. So since the Han Dynasty, greeting cards have been preserved as a traditional form, but the name has changed.