.dem

File Type 1 Generic IconVideo Game Demo File
File Format Proprietary (Valve)
Usage Open manually; may run a program or script when opened
Rank ★ ★ ★  Common
Description

Demo of a commercial video game; typically an in-game recording that serves as an example of the gameplay; used by games such as Half-Life, HalfLife: Counter-Strike, Quake, Hexen, and Unreal Tournament.

Open With
Windows

IconValve Counter-Strike

IconEpic Games Unreal Tournament

Iconid Software Quake

macOS

IconValve Counter-Strike

IconEpic Games Unreal Tournament

Iconid Software Quake

Updated June 9, 2009
File Type 2 Generic IconDigital Elevation Model
File Format Standard (developed by USGS)
Usage Open manually
Rank ★ ☆ ☆  Uncommon
Description

Contains mapping data with elevation information; used by the US Geological Survey.

Open With
Windows

IconESRI ArcGIS for Desktop

IconGolden Software Voxler

IconTatukGIS Viewer

Updated 2007
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