Instant messaging makes it possible to exchange messages between participants almost in real time. In addition to pure text messages, files of all kinds, e.g. photos, video and audio files, Word documents, etc., can also be sent with the help of the corresponding program.
VOIP telephony is the telephony over computer networks, which are developed after Internet standards. Typical information for telephony, i.e. voice and control information for establishing a connection, is transmitted via a data network.
On the one hand, e-mail is a system for the computer-based administration of letter-like messages and their transmission via computer networks, in particular via the Internet. On the other hand, the messages transmitted electronically are also referred to as e-mails.