Bugzilla is a "Defect Tracking System" or "Bug-Tracking System" written in Perl and uses MYSQL database. Bugzilla is a self-hosting web-based general-purpose bugtracker and testing tool originally developed and used by the Mozilla project, and licensed under the Mozilla Public License. Bugzilla provides IT support accountability, telephone support knowledge bases, and keeps tabs on unusual system or software issues. Bugzilla is used by the Mozilla Foundation, WebKit, Linux kernel, FreeBSD, GNOME, KDE, Apache, Red Hat, Eclipse and LibreOffice. Key features of Bugzilla include Advanced search capabilities, E-mail Notifications, Modify/file Bugs by e-mail, Time tracking, Strong security, Customization, Localization. Bugzilla supports MySQL, PostgreSQL and Oracle as database servers.