Matrix is an open protocol for real-time communication. It is designed to allow users with accounts at one communications service provider to communicate with users of a different service provider via online chat, Voice over IP, and Videotelephony. Developed by Matrix.org
License: Open Source
Skype is a widely-used communication platform known for its video conferencing and integration with Microsoft products, but it relies on centralized servers. In contrast, Matrix.org is an open-source, decentralized platform that emphasizes privacy and security, making it suitable for users who prioritize these aspects.