vCard is a file format standard for electronic . vCards are often attached to e-mail messages, but can be exchanged in other ways, such as on the World Wide Web or instant messaging. They can contain name and address information, , e-mail addresses, URLs, , , and audio clips.
In computing, a denial-of-service ( DoS) attack is an attempt to make a machine or network resource unavailable to its intended users, such as to temporarily or indefinitely interrupt or suspend services of a host connected to the Internet. A distributed denial-of-service ( DDoS) is where the attack source is more than one–and often thousands of-unique IP addresses.