Postcards are used for sending short messages with bright pictures on one of its sides and space for writing address on the other. These cards are commercially printed by several companies and can be even customized according to personal specifications. Though postcards are usually sent through postal services, many websites also offer free postcards to select for any occasion and send through email.

Websites offering free postcard services have a number of categories to choose from, depending on the occasion for which the post card would be used. Once the category is chosen the person can choose from the postcards designed for that specific occasion. The email address of the recipient has to be filled in the form provided for sending the card. The sender, after entering all the relevant details, can check the chosen card with all the messages and captions. If satisfied with the card and its messages, design and captions, the sender can send it to the recipient. The card reaches the recipient's mailbox with the heading that an online post card is waiting for the recipient. The sender's name and address is also displayed on opening the card, as it was filled in the delivery information form.

Alternatively, a sender can create and customize a postcard by choosing the option of creating a postcard. The person is then redirected to the section, where a number of options are provided for designing the card. These designs include background, text color, size, type, card layout, and personal message. After customizing the card, the sender can then view the card before finalizing and sending it to the recipient.

This service has become very popular because of its flexibility to select and design postcards and sending them to the recipient for free. Moreover, the cards are sent instantly through emails as compared to the time taken by the postal service. Once delivered, the sender receives a confirmation message stating a successful delivery. Some services also inform the sender when the recipient views the card.