Editing Turing machine (section)

====Interaction====
In the early days of computing, computer use was typically limited to [[batch processing]], i.e., non-interactive tasks, each producing output data from given input data. Computability theory, which studies computability of functions from inputs to outputs, and for which Turing machines were invented, reflects this practice.

Since the 1970s, [[interactivity|interactive]] use of computers became much more common.  In principle, it is possible to model this by having an external agent read from the tape and write to it at the same time as a Turing machine, but this rarely matches how interaction actually happens; therefore, when describing interactivity, alternatives such as [[Input/output automaton|I/O automata]] are usually preferred.