Computers used in these markets go where the action is, everywhere in the world, indoors and out, regardless of the weather. Military organisations use computers with the highest requirements for access and reliability. There's usually no time for replacements in the heat of battle, and the environment changes with the whims of combat. Government users can include for example, Investigative or Intelligence units, Customs, or others that use their computers in the field for data-collection of fact-finding.

Any factory environment can be full of dust, conductive particles, corrosive vapors or electrical interferences. Due to these facts and compulsory demands for shock and vibration, computer systems have to be designed and built in ways that will reduce down-time in the production line.

Nowadays, computers have become an integrative part of nearly every new vehicle; they thus can be found in fleet management systems that use GPS and GPRS or WLAN communications. At sea, the harbour management system assists the navigation to guiding ships safely and efficiently into their berths. Cargo handling systems are managed by small hand-held computers that can communicate with an enterprise system.

Emergency Management units, Disaster teams or Disease Control units have to be able to rely on computer power that won't fail, regardless of geographic locations or weather conditions. Homeland Security units operate on land, at sea or in the air to monitor and protect borders or strategic targets.

Computers for installation or service of products in the field, measurement of environmental variables at sea, in the air, in space, in the field and for cases where the collection of data collected is more worth than the computer itself. These computers must be designed for high demands on reliabilty; furthermore, the systems must be flexible and survive in a wide range of environments.