The state in which a device with a communication interface is not ready to receive or send data over this interface is referred to as offline . The opposite of that is online . The ON / OFF scale assumes that users can only be considered offline if they do not have any web-enabled devices or if they are completely switched off and data tracking is excluded.
A typical example of an application that works mainly offline are e-mail programs that pick up incoming e-mails and send new ones during a short connection time . The main work - reading and writing - can be done without a connection during the time. Feed readers and offline browsers work in a similar way .
Another example is the creation of sequence programs for systems or machines while they are working. The program may be written and tested offline on an external computer using 3D CAD data in order to be imported again at a later point in time (during a service or component change).
Websites can also be offline that have ceased to operate or that certain pages are no longer available there.