Fiji is just ImageJ: a distribution of ImageJ (and ImageJ2) together with Java, Java 3D and a lot of plugins organized into a coherent menu structure. The main focus of Fiji is to assist research in life sciences. It is a free, open-source, community-driven project.
has interaction level
has programming language
has entry curator
GPL v2 (and others: http://fiji.sc/Fiji:About)