Racket (formerly PLT Scheme) is a programming language suitable for implementation tasks ranging from scripting to application development, including GUIs, Web services, etc. It includes the DrRacket programming environment, a virtual machine with a just-in-time compiler, tools for creating stand-alone executables, the Racket Web server, extensive libraries, documentation for both beginners and experts, and more. It supports the creation of new programming languages through a rich, expressive syntax system. Example languages include Typed Racket, ACL2, FrTime, and Lazy Racket.
Marble is a Virtual Globe and World Atlas that you can use to learn more about Earth: you can pan and zoom around, and you can look up places and roads. A mouse click on a place label will provide the respective Wikipedia article. It's also possible to measure distances between locations or watch the current cloud cover. Marble offers different thematic maps: a classroom-style topographic map, a satellite view, street map, earth at night, and temperature and precipitation maps. All maps include a custom map key, so it can also be used as an educational tool for use in classrooms. For educational purposes, you can also change the date and time and watch how the starry sky and the twilight zone on the map change. Marble also features multiple projections: choose between a flat map ("Plate carré"), Mercator, or the globe.