One way of conceptualising this is

One way of conceptualising this is to identify the types of control that users might have. In doing this, I would suggest two dimensions along which interactivity operates.
Firstly, time and space; secondly input and output.
Control over time and space
Where broadcast required the user to be present at a particular time, and print to wait for the next edition, technologies such as Video On Demand (VOD), personal video recorders (PVR) such as Sky+ and TiVo, podcasts, mobile phones and websites allow the audience to consume at a time convenient to them. The PDF newspaper is another less successful development that also allows readers to avoid the dependence on print and distribution cycles.
Similarly, whereas television has normally required the user to be physically present in front of a static set, the spread of mobile phones, mp3 players and portable mpeg players and wifi laptops allow the audience to consume in a space convenient to them. Portable radio and portable newspapers have always had this advantage.
In mapping these it becomes clear that control over time and space tends to centre on hardware, and miniaturisation.
Control over input and output
With linear media such as TV, radio and print, the consumer relies on the ability of the producer, editor, etc. to structure how content is presented – in other words, the output. New media allows the audience to take some of that control. Examples include:
• At a basic level, hyperlinks allow the reader to dictate their experience of ‘content’ through their choice of clicks.
• With online video and audio, the user can pause, fast-forward, etc. – and if it has been split into ‘chunks’, the user can choose which bit of a longer video or audio piece they experience.
• RSS allows users to create their own media product, combining feeds from newspapers, broadcasters, bloggers, and even del.icio.us tags or Google News search terms.
• Database-driven content allows the user to shape output based on their input – e.g. by entering their postcode they can read content specific to their area. At a general level search engines provide a similar service.
• And Flash interactives allow the user to influence output in a range of ways. This may be as simple as selecting from a range of audio, video, text and still image options. It may be playing a game or quiz, where their interaction (e.g. what answers they get right, how they perform) shapes the output they experience.