He is talking about a 2D game engine. There are several of those around, but how useful they'll be depends on your experience.
Slick - http://slick.cokeandcode.com/
Requires more experience, but the features are more advanced, and there's less convenience code (good or bad depending on your situation). But this is good for games that are performance oriented and would like to take advantage of OpenGL. Open source.
GTGE - http://www.goldenstudios.or.id/products/GTGE/
Easier to use for someone starting out. More convenience classes but on the flip side, less minimalist than Slick. Not open source.