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.
WhatsApp Messenger is a proprietary cross-platform, encrypted, instant messaging client for . It uses the Internet to send , documents, images, video, user location and audio messages to other users using standard cellular networktelephone number.
Electronic mail, most commonly called email or e-mail since around 1993, is a method of exchanging digital messages from an author to one or more recipients. Email operates across the Internet or other .
Conversation threading is a feature used by many email clients, , , and in which the software aids the user by visually grouping messages with their replies. These groups are called a conversation, topic thread, or simply a thread. A discussion forum, e-mail client or news client is said to have a "conversation view", "threaded topics" or a "threaded mode" if messages can be grouped in this manner.