On-Demand refers to a service or feature which addresses the user's need for instant gratification and immediacy of use. In most cases the value proposition for an on-demand service is wrapped up in the fact that the user or consumer of the service avoids a significant up-front financial investment and instead participates in a "pay as you go" plan - a model which makes on-demand services frequently more affordable for users.
Some types of On-demand services include:
- Video on demand is a type of video or movie service which allows the viewer to access the media immediately upon subscription, such as streaming Internet or pay-per-view television offerings.
- On-demand computing may also be referred to as Utility computing, and most frequently refers to a type of computing service where the actual software is presented to the user, once a subscription to the service is successfully processed. In a typical "on-demand" computing model, the software is not actually installed at the user device, rather it is accessed via the Internet or centralized access point.
- On-demand software is typically delivered by an application service provider. This type of service offering is also frequently referred to as Software as a Service.
- Print on demand, also known as publishing on demand, is a type of publishing method used by low-quantity book publishers, whereby authors may have their materials available for print publication without investing the up-front costs of initial publication.