An e-card is similar to a postcard or greeting card, with the primary difference being it is created using digital media instead of paper or other traditional materials. E-cards are made available by publishers usually on various Internet sites, where they can be sent to a recipient, usually via e-mail.

E-cards are digital "content", which makes them much more versatile than traditional greeting cards. For example unlike traditional greetings, e-cards can be easily sent to many people at once or extensively personalized by the sender. Conceivably they could be saved to any computer or electronic device or even viewed on a television set, however E-card digital content has not yet progressed as far as digital video or digital audio in terms of varied usage.

Typically an e-card sender chooses from an on-line catalog of e-cards made available on a publisher's web site. After selecting a card, the sender can personalize it to various degrees by adding a message, photo, or video. Finally the sender specifies the recipient's e-mail address and the web site delivers an e-mail message on behalf of the sender to the recipient.

Some e-cards are intended to be printed out rather than sent via e-mail, to most people however are not considered e-cards and are simply home-made greeting cards. The advantage to this over a traditional greeting sometimes can be cost savings, or sometimes simply the ability to "create" something for the recipient rather than choosing a fully completed paper card.