GMW files are files associated with Global Mapper, a mapping software developed by Blue Marble Geographics.  GMW stands for Global Mapper workspace and files that have the GMW extension typically contain map-related data like images, layers of elevations, and projections among many other data. These files are the main files associated with the Global Mapper software which is considered one of the most powerful and comprehensive source of mapping and information and GIS or geographic information system.

When users encounter GMW files, the Global Mapper software may have been already installed in one’s computer.  Many files that have the GMW extension have map and image displays of a specific geographic location.  Along with the visual or map display, other details may also be embedded or stored in the same GMW file.  Several digitized layers such as data on mountain ranges or lakes may also be contained in the GMW file.  People familiar with the Global Mapper software utility may also add information using the GMW file.  New points or lines to be included in the mapping or geographic information may also be indicated using the software’s GMW file.

For users who are not familiar with Global Mapper and its associated GMW files, they may just need to close down or ignore it when they encounter files with GMW extensions. For more savvy users and those that use the Global Mapper software, they may wish to check on some details of GMW files by opening them using Notepad.  With this technique, users will be able to check the details inside GMW files.  Typical information stored on GMW files when opened as a text file includes scripts and program commands on how mapping data is displayed. For people familiar with programming scripts, some editing may be done onto the text version of the GBW file via the Notepad tool.