What is DWG?
DWG is AutoCAD’s native binary drawing format, created by Autodesk, and the de facto standard for CAD drawings such as site plans, survey data, and engineering designs.
A DWG file stores CAD entities — lines, polylines, arcs, circles, text, blocks, and dimensions — organized on named layers, together with drawing metadata and viewport settings. It is a closed, proprietary binary format that changes across AutoCAD releases, so reading it reliably requires licensed technology: GeoConvert uses the Open Design Alliance (ODA) engine, the same technology major CAD vendors build on. Converting DWG to GIS formats extracts the geometry and layer structure into features you can style and analyze.
What is KML?
KML (Keyhole Markup Language) is an XML-based format for expressing geographic annotation and visualization, adopted as an OGC standard and popularized by Google Earth.
KML describes Placemarks, geometries (points, lines, polygons), and their presentation using an XML tree that also supports folders for organization, rich styling (icons, colors, line widths, fills), balloon descriptions, and ground overlays. It is designed for display and sharing rather than analysis, and is opened natively by Google Earth, Google Maps, and most GIS packages. Because it targets a single global view, it has no concept of reprojection.
Coordinate systems
Like DXF, a DWG drawing carries no coordinate reference system — coordinates are plain model units in whatever local or projected system the drawing was authored in. Converting to GIS usually means assigning the correct source CRS so the geometry lands in the right place on the map.
KML coordinates are always geographic WGS84 longitude, latitude, and (optionally) altitude in that order; the format has no CRS or projection field, so any data written to KML is expressed in EPSG:4326 by definition.