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 KMZ?
KMZ is a ZIP archive that packages a KML document (conventionally named doc.kml) together with any assets it references, such as icons, images, and overlays.
Structurally a KMZ is just a compressed container: unzip it and you get a main doc.kml plus an optional folder of supporting files. Zipping typically shrinks verbose KML text substantially and keeps a placemark set and its custom icons together as one shareable file, which is why Google Earth exports KMZ by default. Everything true of KML applies to the KML inside a KMZ; the wrapper only adds compression and asset bundling.
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.
Because the payload is ordinary KML, a KMZ is inherently WGS84 (EPSG:4326) longitude/latitude/altitude, with no projection metadata and no possibility of reprojection inside the format.