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 large groups and emphasizes privacy, while AIM focuses on instant messaging and integrates well with AOL services but lacks advanced conferencing features. Jitsi is ideal for large, secure meetings, whereas AIM is suitable for casual chats and basic video calls.