The periodic table - classification of elements. Definitions of groups, periods, alkali metals, alkaline earth metals, halogens, and noble gases. How metals, non-metals, and metalloids can be identified by the position on the periodic table. Created by Jay. Introduction to the periodic table. The periodic table - classification of elements. Groups of the periodic table. Counting valence electrons for main group elements.
OPENBook is software developed for blind and visually impaired individuals to read, edit, and manage scanned images from books, magazines, manuals, bills, newspapers, and other printed documents. It essentially turns your computer system into a scanning and reading machine.
OpenStreetMap is a free geographic data. OpenStreetMap built by volunteers largely from scratch and released with an open-content license. The OpenStreetMap License allows free (or almost free) access to our map images and all of our underlying map data. The project aims to promote new and interesting uses of this data.s mentioned above, we have created various map editing tools. In fact OpenStreetMap is powered by open-source software from its slippy map interface to the underlying data access API (a web service interface for reading and writing map data).