An activity, device, service or system whose failure or disruption will cause a failure in business operations. For example, an online business's mission critical is its communication system. A water filtration company will cease to function if its water filter system is down and a bakery will have to shut down if it does not get gas or electricity services to fuel the ovens. In this case, the critical function of this business is to bake desserts and it’s mission critical is the power supply required to run the ovens. This is a popular term used to describe the essential services required for day-to-day operations. If a business operation cannot be interrupted under any circumstance without hurting production, then this operation is considered the business’ mission critical because it is indispensable. Databases and process control software are considered mission critical to a company that runs on mainframes or workstations. Emergency call centers, computerized hospital patient records, data storage centers, stock exchanges and any other operations dependent on a computer and communication systems have to be protected against downtime or shutdowns due to the system's mission-critical functions.