Open source Access to the source code enables you to modify OpenX Source™ or create new features using the plug-in framework. You can have more revenue by making your inventory available to higher-paying advertisers via one-click integration with OpenX Market. Configurable targeting options let you target campaigns to specific site visitors at specific times of day. The reporting let you know which ads you served, how they performed and how much revenue you generated.
OpenX is the world’s leading independent provider of digital advertising technology that enables businesses to manage and maximize their ad revenue.
Actually, it’s three ad serving products;
OpenX Enterprise™
OpenX OnRamp™ and
OpenX Source™
...that serve every type of publisher — from massive global websites serving billions of ads, to niche blogs. Here is a comparison chart:

These products provide a comprehensive revenue generation platform by combining ad serving with a unique ad exchange called OpenX Market. OpenX ad serving products are used by more than 200,000 websites in more than 100 countries and serve more than 350 billion ads monthly. OpenX Market reaches more than 400 million monthly unique users worldwide.

