Adium

vs

Zoom

Jitsi is an open-source project and software toolset that allows you to easily build and deploy secure video conferencing solutions. At the heart of Jitsi are Jitsi Videobridge and Jitsi Meet, which let you have conferences on the internet, while other projects in the community enable other features such as audio, dial-in, recording, and simulcasting.  Jitsi supports popular protocols such as SIP, XMPP/Jabber, ICQ/AIM, Windows Live, Yahoo!, Google Hangouts, OTR, ZRTP and more.

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Pidgin is a chat application which lets you log into accounts on multiple chat networks simultaneously. Pidgin is developed and released fully free and open-source and provides a plugin architecture that allow anyone to build extensions and connections to new networks and third-party services.

Microsoft Teams is your hub for teamwork, it brings together everything a team needs from chat and threaded conversations, meetings & video conferencing, calling, and content collaboration. With you can instantly go from group chat to video call with the touch of a button. Securely connect, access, share, and coauthor files in real time. While staying organized by keeping notes, documents, and your calendar together.

Join.me is a screen sharing, online meetings and team collaboration application. With join.me you and your team can collaborate on projects over audio and video conferencing by phone or internet (VoIP) in real time. Join.me is perfect for remote work and let's team come closer togher.

Skype is a telecommunications application that specialize in providing video chat and voice calls between computers, tablets, mobile devices and consoles. The software allows you to connect with friends and business colleges worldwide. Skype provides free online calls, messaging, affordable international calling to mobiles or landlines and Skype for Business for effective collaboration among teams.