The Internet currently demands a high level of motivation and interaction from its users, as it requires them to actually go out and track down information for themselves using a variety of tools which are available. A typical web search might involve a long sequence of actions and events: a user will need to access the site of a web search engine by typing a URL into their web browser, wait for the home page to appear, type in their search query, wait for the search to be performed and results displayed, scroll through the list of results, check out some of the hits returned by accessing the relevant web pages and review the search and perhaps refine it if the information displayed isn't relevant to their information needs. This process may then have to be repeated again using another search engine if more information is still required. Such a process can be extremely time-consuming, and often frustrating.
Push technology, however, emulates the model of a television broadcast. Television is largely a passive rather than an active medium: most of us know, for example, that Coronation Street will be delivered to us by TV broadcasters at certain times of the week on a certain channel. All we have to do is switch on at the correct time and sit down to watch.
Push technology brings this model of information delivery to the Internet: it involves information actually being pushed out or broadcast to Internet users so that they don't actively have to search and pull it in for themselves. Typically, a user could initially choose to subscribe to a number of channels - just as we might choose to subscribe to cable or satellite TV. These channels could be content delivery services maintained by commercial information providers on the Internet. The information providers make a viewer freely available for download from their web sites, and the user installs this viewer on their PC. Information content can then be broadcast out to subscribers whenever the information provider updates its information database; and the user will receive regular updates of information without having to do any active web browsing. to seek this information out for themselves.
Push technology has a number of added advantages over the television model of information delivery. In particular, the user can actually customise what is delivered and choose how and when they want to view this information. A user can set up a personal profile which can then be used to ensure that only information which is relevant to their individual interests is delivered. Hyperlinks can also be provided so that users can follow up a link to get further information on a topic. It is also possible to specify how frequently updates are required. A variety of objects can also be delivered - these might include java applications, multimedia objects, text or even software.
Various services are now available which use push technology to deliver information content. The PointCast Network  appears to be at the forefront of this development, with a service which broadcasts international news, stock information, industry updates, weather information and sports and entertainment coverage. PointCast take their news sources from other large information providers such as CNN, Time Magazine and Reuters. Yahoo! also has an application called My Yahoo! News Ticker  which delivers news information, using a personal profile set up by the user to filter information. Both of these services are freely available for download from the appropriate web pages. These services deliver information using a specially customizable screen saver, or a dedicated taskbar on a Windows desktop.. This means that a user can receive the latest updates whilst working on other projects rather than actively web surfing.
However, the big push for Push is likely to come when Netscape and Microsoft release Push-enabled versions of their web browsers later this year. Netscape is developing an application called Constellation, which will feature customisable areas of the desktop which can display pushed information from various different channels. Microsoft Internet Explorer 4.0 will use ActiveX controls to enable information providers to push content out to users . Currently all of the products available for Push use a separate application for content viewing, so it is likely that the technology will take off in a big way once it becomes integrated into a standard web browser.
Obviously an area where such services are already starting to prove useful is in the delivery of news services, and many big American news organisations such as CNN are already starting to get involved in delivering services in this way. However, many of the services currently available are aimed at American users, and content tends, therefore, to be US biased. Push is also very useful for delivering `just in time' information - up to the minute sports and entertainment coverage, industry reports, stock market quotes, weather reports etc. But how might such a service be useful to a UK academic user looking for research materials? Push could potentially be put to good use in eLib information gateway projects such as OMNI  and EEVL: imagine how useful it would be if you could receive the latest updates from an information gateway of your choice whenever new resources were added to your own particular area of interest, without having to go online to check for changes on a regular basis.