1.  Field of the Invention
The present invention relates to the presentation of digital content on personal communication devices.  In particular, the present invention relates to systematic scheduling of the presentation of digital content on personal communication devices. 
2.  Background Information
Over the last decade, there has been a tremendous increase in demand for new and better means of communicating and transferring data among consumers over communication networks.  The Internet has played an important role in satisfying this demand, in that its development has spawned many new modes of communicating and sharing data, such as e-mail, chat, instant messaging, and video messaging.  During its early development, consumers could only access the Internet and these new forms of digital content from a computer that was hard-wired to the Internet, either over a local area network, or via a modem.  Recently, there has been a shift in consumer demand toward wireless communication and data sharing.  People want access to all of these forms of communication and data transfer not only while they are at their desks, but also when they are on the move. 
Many companies have tried to meet this demand by providing cellular phones and other wireless communicating devices which can transmit and receive Internet-type communications in addition to voice communications.  However, because such phones have small display screens and limited data input devices, they typically rely on scaled down data transmission protocols, such as the Wireless Application Protocol (WAP).  Although WAP devices can transmit textual and graphical data, they are extremely limited in bandwidth.  As such, these devices and the digital content available with them do not provide a very interesting user experience. 
Aside from the problem of providing a wireless device with which consumers can communicate using these Internet-type modes of communication, there is also the problem of determining what information to provide.  The Internet has quickly become one of the world""s largest sources of knowledge and information.  The enormous size and scope of the Internet and other information networks often makes it impossible to find relevant information in a reasonable amount of time.  The difficulty of obtaining relevant information from the Internet and other information networks in a timely fashion has given rise to the development of a wide variety of products and services which locate and sift through large volumes of data in an effort to disseminate particular information which is relevant to particular consumers.  For example, consumers can subscribe to certain services which locate and periodically broadcast specified information to their subscribers.  This technology is often referred to as xe2x80x9cpushxe2x80x9d technology, in that the information, or digital content, is pushed from the information provider to the subscriber. 
It is not uncommon for push-technology service providers to have each subscriber fill out an initial questionnaire at the beginning of the subscription in order to obtain certain information about the subscriber.  Such questionnaires typically include questions directed to the subscriber""s biographic, demographic, and economic background.  The digital content that is broadcast by these service providers to their subscribers is typically controlled solely by the service provider, with no input from the subscriber, other than the subscriber""s initial questionnaire or when the subscriber updates his profile.  These systems are not designed for ongoing interaction between the subscriber and the service provider.  Although such systems can provide periodic broadcast of digital content or information, such as the transmission of a daily e-mail of news or information, they are not designed to provide the most appropriate digital content at the most appropriate time for the subscriber.  Other than the subscriber xe2x80x9cunsubscribing,xe2x80x9d the service provider has no way of knowing whether the subscriber is still interested in the digital content offered by the service. 
Although the devices and systems discussed above represent great strides in the areas of communication and presentation of digital content over personal communication devices, many shortcomings remain. 
There is a need for a method and apparatus with which digital content may be systematically scheduled and presented on personal communication devices. 
Therefore, it is an object of the present invention to provide a method and apparatus for systematically scheduling and selectively presenting digital content on personal communication devices. 
It is another object of the present invention to provide a method and apparatus for systematically scheduling and selectively offering digital content for presentation to users, wherein the digital content is generated, organized, stored, and rated by the users over a communication network. 
It is another object of the present invention to provide a method and apparatus for systematically scheduling and selectively offering digital content for presentation to users, wherein the digital content is generated, organized, stored, transmitted over a communication network to a client device, and rated by the users. 
It is another object of the present invention to provide a method and apparatus for systematically scheduling and selectively offering digital content for presentation on a client device, wherein the digital content is generated, organized, stored, profiled, compared to a contextual user profile, transmitted to the client devices over a communication network, and rated by the users. 
These objects are achieved by providing a method and apparatus wherein a software scheduling agent resides on a communication network and/or client device, such as location-aware wireless communication appliances, television set top boxes, or other end user client devices.  The software scheduling agent is part of a probabilistic modeling system in which the scheduler operates to perform constrained random variation with selection.  Digital content is generated, organized, and stored on the communication network and/or the client devices.  An electronic digital content wrapper, which holds information in the form of data and metadata related to the digital content is associated with each item of digital content.  Contextual profiles for each user and each item of digital content are established by the users and the network and maintained by a service provider on the communication network.  The software scheduling agent compares the contextual digital content profile for each item of digital content to the contextual user profile for each user to determine which digital content should be offered for presentation to each user.  The comparison and determination of which items of digital content should be offered for presentation to which users is performed by a process of constrained random variation.  After the software scheduling agent determines which items of digital content would most likely be relevant or interesting to the user, the digital content is transmitted, either in whole or in part, at predetermined times over the communication network to the appropriate client devices.  The digital content is then stored, either in whole or in part, in cache memory on the client device until an appropriate time when the digital content is digitally packaged and presented to particular users over the users"" client devices. 
The present invention has many advantages over conventional methods and apparatuses for transmitting digital content to personal communication devices.  First and foremost, the present invention is not merely a method of broadcasting digital content to an indiscriminant collection of subscribers.  The present invention is a tool with which the user can play an active role in the dissemination and presentation of digital content.  The present invention uses a scheduling agent that is based upon a probabilistic modeling system.  The contextual digital content profiles and the contextual user profiles are continuously updated to ensure that there is a high probability that the user will be presented with digital content that he finds relevant and interesting.  The user plays an ongoing active role in the systematic scheduling of digital content by rating the digital content as it is presented.  Although the scheduling system is very sophisticated, the rating procedure is very intuitive and non-intrusive.  The system is designed to obtain valuable opinion information from the user without intruding into the user""s experience.  Through the rating system of the present invention, the user has a certain level of control over which digital content is offered to himself and others on the system.  This ensures that the user will not only continue to participate in the experience, but take an active role in the dissemination of digital content, thereby building community.