Bugzilla is a general-purpose bug-tracking tool originally developed and used by the Mozilla Foundation. Since Bugzilla is web-based and is free software / open source software, it is also the bug tracking tool of choice for many projects, both open source and proprietary.

Bugzilla relies on an installed web server (such as Apache) and a database management system (such as MySQL or PostgreSQL) to perform its work. Bugs can be submitted by anybody, and will be assigned to a particular developer. Various status updates for each bug are allowed, together with user notes and bug examples.

Bugzilla's notion of a bug is very general; for instance, mozilla.org uses it to track feature requests as well.

Release notes such as those for Bugzilla 2.18.3 indicate the exact set of dependencies, which include:

• A compatible database server (often a version of MySQL)
• A suitable release of Perl 5
• An assortment of Perl modules
• A compatible web server such as Apache (though any web server that supports CGI can work)
• A suitable Mail Transfer Agent such as Sendmail, qmail, Postfix, or Exim

• Bugzilla Home Page
• Bugzilla Live Demo
• Step-By-Step Bugzilla Installation On Windows
• Mozilla.org's Bugzilla Installation
• Wikimedia's Bugzilla
• Open Directory - Bug Tracking Software
• Wiki on Modifying Bugzilla
• Bugzilla Installation List Tops 400