AA Panel (aapanel.com) is a free server management panel from China that helps administrators easily manage servers, websites, and applications through a web interface, with integrated website, database, email, FTP, and SSL management.
Ajenti is an open-source Linux server management panel created in 2012 by Russian developer Eugene Pankov, MIT-licensed and free with 8k+ GitHub stars, lightweight and plugin-rich for visual administration on low-end VPS.
aaPanel is the international edition of BT Panel, founded in 2018 in Hangzhou by the Bao Wang team, free and open source with 1,000,000+ users, offering one-click LAMP/LNMP deployment and free SSL.
ZPanel is a UK-origin open-source virtual hosting control panel that once delivered integrated hosting management on Windows and Linux, but the project is now discontinued and suitable only for study and legacy environments.