Jitsi (formerly SIP Communicator) is a free and open source multiplatform voice (VoIP), videoconferencing and instant messaging application. Developed by University of Strasbourg (France), plus many others.
License: Open Source
Jitsi is a versatile, open-source video conferencing tool that supports high-quality audio and video, screen sharing, and group calls, making it ideal for collaborative work and larger meetings. In contrast, the telephone is a traditional communication method that excels in simplicity and reliability for voice calls but lacks modern features like video support and screen sharing, making it less suitable for interactive discussions.