- Reading time: 5 minutes / whole rubric: 86 minutes -

Here some explanations:

“Everybody knows that” - to claim that is arrogant! Also in connection with instant messages (chat) special abbreviations and terms are used again and again:

Abbreviation/Term Description
anonymity without reference to identity / without personal data / nameless / unknown / disguised / also: “incognito” >> description <<
channel A public and openly accessible chat room or simply “public chat” for short
see also ->muc
API An interface to exchange information between applications/programs >> more <<
Abbreviation for: „Application Programming Interface“ / a mainly technical term
Electron System in which an application is embedded in its own browser >> more <<
Flutter System from google in which an application is embedded >> more <<
IETF / Internetstandard / IESG The IETF is a neutral organization with a wide variety of members and regulated processes, which carries out a great deal of quality assurance work and is recognized worldwide for this.
An Internet standard is a network protocol specified by the Internet Engineering Task Force (IETF) for use on the Internet. Es handelt sich dabei um einen offenen Standard, der sich im praktischen Einsatz bewährt hat und von einer breiten Öffentlichkeit unterstützt wird. Jeder Internetstandard besteht aus einem oder mehreren Request for Comments (RFC); jedoch nicht jedes RFC stellt einen Internetstandard dar.
Recognition as an Internet standard is decided by the Internet Engineering Steering Group (IESG).
An example of an Internet standard is the Domain Name System (DNS), which comprises two Request for Comments RFC 1034 and RFC 1035 as STD 13. This Internet standard is useful, technically mature, and enjoys support from the Internet community.
DNS extensions such as EDNS0 are managed as separate standards.
Source: https://de.wikipedia.org/wiki/Internetstandard (external)
Jabber Chat system originally developed by Jabber; today corresponds to the standard protocol XMPP; not to be confused with “Cisco Jabber”!
JID name/designation for a chat account or a chat / Jabber identifier / abbreviation of „Jabber-ID“
Format: „acoount@server.tld“ or „chatroom@xyz.server.tld“ / Example: „im@jabber.de“ or „freie-messenger@conference.jabber.de“
LAN Local Area Network
muc Group / Group Chat / Room / Chat / Conference
Chats can be closed/open, private/public personal/impersonal and with/without write permissions respectively.
Abbreviation for “multi user chat / a mainly technical term
NAT The translation of private IP addresses to a public IP address behind routers is done by NAT, which can lead to problems with Internet telephony with WebRTC.
Abbreviation for: “Network Address Translation
OMEMO XMPP extension (-> XEP) for secure end-to-end encryption even with multiple end devices, even if they are offline. Uses the same technology as “Signal”.
Abbreviation for: “OMEMO Multi-End Message and Object Encryption”
P2P Direct connection >> more <<
Abbreviation for: Peer to Peer
push / push notification Push notifications are used to indirectly start apps that have been terminated by the system. >> more <<
RFC Request For Comments; vgl. ->IETF
STUN Technical help to exchange the IP addresses of the call partners in Internet telephony if they are not in the same network. >> more <<
Abbreviation for: “Session Traversal Utilities for NAT
TURN Technical help to exchange the IP addresses of the call partners in Internet telephony when a firewall is used. >> more <<
Abbreviation for: “Traversal Using Relays around NAT
UI User Interface
URI Uniform Resource Identifier“ / identification mark
WAN Wide Area Network that can extend worldwide in larger companies; same technology as ->LAN
WebRTC Communication protocol for Internet telephony >> more <<
Abbreviation for “Web Real-Time Communication
XEP Standardized XMPP Extensions / XMPP Extension Protocols
XMPP Extensible messaging and presence protocol based on ->XML.
XML Extensible Markup Language

In general:
Technical terms and abbreviations should only be used if all participants understand them. It is arrogant to assume that one's own knowledge would also be general knowledge.