WebRTC (Web Real-Time Communication) is an API definition drafted by the World Wide Web Consortium (W3C) that supports browser-to-browser applications for voice calling, video chat, and P2P file sharing without the need of either internal or external plugins.

Voice over IP (VoIP, abbreviation of voice over Internet Protocol) commonly refers to the communication protocols, technologies, methodologies, and transmission techniques involved in the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. wikipedia.org

FreeSWITCH is a free and open source communications software for the creation of voice and messaging products. It is licensed under the Mozilla Public License (MPL), a free software license. wikipedia.org

Voice over IP (VoIP, abbreviation of voice over Internet Protocol) commonly refers to the communication protocols, technologies, methodologies, and transmission techniques involved in the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. wikipedia.org

Node.js is a software system designed for writing highly-scalable internet applications, notably web servers. Programs are written in JavaScript, using event-driven, asynchronous I/O to minimize overhead and maximize scalability. wikipedia.org

"TypeScript is a free and open source programming language developed and maintained by Microsoft. It is a strict superset of JavaScript, and adds optional static typing and class-based object-oriented programming to the language. Anders Hejlsberg, lead architect of C# and creator of Delphi and Turbo Pascal, has worked on the development of TypeScript." wikipedia.org

The Session Initiation Protocol (SIP) is an IETF-defined signaling protocol widely used for controlling communication sessions such as voice and video calls over Internet Protocol (IP). wikipedia.org

FreePBX is a GUI (graphical user interface) that controls and manages Asterisk, an open source telephony engine software.

JavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles. wikipedia.org

Twilio is a cloud communications IaaS (Infrastructure as a Service) company based in San Francisco, California. Twilio allows software developers to programmatically make and receive phone calls and send and receive text messages using its web service APIs.

Asterisk is a software implementation of a telephone private branch exchange (PBX). It allows attached telephones to make calls to one another, and to connect to other telephone services including the public switched telephone network (PSTN) and Voice over Internet Protocol (VoIP) services. wikipedia.org

The Kamailio SIP server is a Open Source software for building SIP services such as a SIP proxy, SIP Presence Server, and SIP location server.

A database administrator (short form DBA) is a person responsible for the installation, configuration, upgrade, administration, monitoring and maintenance of physical databases.