a required characteristic of an online real-time system is
Real-time operating system A key characteristic of an RTOS is the level of its consistency concerning the amount of time it takes to accept and complete an application's task; the variability is jitter.[1] A hard real-time operating system has less jitter than a soft real-time operating system. The chief design goal is not high throughput, but rather a guarantee of a soft or hard performance category. An RTOS that can usually or generally meet a deadline is a soft real-time OS, but if it can meet a deadline deterministically it is a hard real-time OS.[2]
Information system An information system (IS) is an organized system for the collection, organization, storage and communication of information. More specifically, it is the study of complementary networks that people and organizations use to collect, filter, process, create and distribute data. Further, "[a]n information system (IS) is a group of components that interact to produce information. It focuses on the internal rather than the external." Information system can also be described as a combination of hardware, software, data, business process and functions which can be used to increase efficiency and management of an organization. Information Systems is the expression used to describe an Automated System (which may be referred to as a Computerized Information System), be it manual, which covers people, machines or organized methods to collect, process, transmit and disseminate data representing information for the user or client.[1]