Abstract: Providing presence information within digital items is described. In one example, a server system receives presence information from a plurality of client devices. The presence information indicates a portion of a digital item associated with at least one user of each respective client device. The server system also receives a user identification request from a requesting client device to identify one or more users of the plurality of client devices associated with a particular portion of the digital item. Additionally, the server system identifies a user of a particular client device associated with the particular portion of the digital item based on the presence information of the particular client device and sends an identifier of the user of the particular client device to the requesting client device.

Abstract: Techniques for aligning content items with one another are described herein. These techniques may align different versions of a same content item for the purpose of identifying differences between the versions, identifying commonalities between the versions, mapping annotations made in one version to the other version, aggregating annotations across the different versions, or for any other reason. The content items may include electronic books, songs, videos, documents, or the like.

Abstract: A meaning of a term is determined using the contents of a corpus of books through use of metadata about the books within the corpus, terms in the same work which provide context, and so forth. Users may query to determine the meaning of a term. Users may also build vocabulary skills by testing as well. A changing meaning of a term over time may be determined and utilized as well. Searches are facilitated by the enhanced ability to determine meaning of the terms, particularly in context. Feedback from the searches may also be used to refine future searches.

Abstract: A popular highlight may be presented to a user who wishes to make the popular highlight a personal user highlight. Upon activation of a control, a personal user highlight is generated from the popular highlight. The user may then manipulate the resulting personal user highlight as they would any other user highlight.

Abstract: Techniques for ranking electronic content items include analyzing annotations made in the content items. Specifically, the number of annotations and the number of people making the annotations can be analyzed to produce a popularity ranking of different content items.

Abstract: A popular highlight may be presented to a user who wishes to make the popular highlight a personal user highlight. Upon activation of a control, a personal user highlight is generated from the popular highlight. The user may then manipulate the resulting personal user highlight as they would any other user highlight.

Abstract: In some implementations, a user may select a category, attribute or term related to content item. During presentation of the content item, an electronic device may visually distinguish (or, alternatively, hide) at least one portion of content associated with the selected category, attribute or term. In some examples, a user interface may be displayed to enable the user to select one or more categories, attributes, or terms related to the content item. The user interface may further enable the user to select a graphics scheme to be used for visually distinguishing at least one portion of content corresponding to the selection. Selection information identifying a portion of content to be visually distinguished or hidden may be sent to a content provider, such as for synchronization with other instances of the content item on other devices of a user, or for aggregation of the selection information by the content provider.

Abstract: In some implementations, a digital work provider provides a digital work and supplemental information related to the digital work for delivery to an electronic device. For example, the digital work provider may parse a digital work to identify objects in the digital work. The digital work provider may generate supplemental information for the digital work based on the objects. For example, the supplemental information may include an index identifying locations of occurrences of the objects identified in the digital work. The supplemental information may further include prestored content related to one or more of the objects. For instance, the digital work provider may obtain the prestored content from one or more authoritative network resources. The electronic device may display the supplemental information in response to a user selection of an object in the digital work during display of the digital work.

Abstract: A method is provided for presenting a written work. A character identity is recognized within a written work. Presentation information for the written work, such as a graphical scheme or an electronic voice, is determined based on the character identity. The presentation information is provided to a user computing device. The user computing device renders the written work or a portion thereof using the presentation information.

Abstract: As described herein, passages in a digital work (e.g., eBook, music, movie, picture, etc.) may be highlighted and questions pertaining to those highlights may be developed. The highlights are collected centrally and subsequently supplied to users along with the digital works. Users may further ask questions pertaining to the highlighted passages, and these questions are associated with the highlights. Answers to the questions may also be discovered and provided to the users.

Abstract: Digital items may be lent from one user to another. A lending system may facilitate matching users that have a digital item to lend with users that wish to borrow a digital item. Each user may have a reputation associated with his or her lending behavior that is represented as a lending metric. The lending metric may show whether a given user is primarily a lender or borrower of digital items. Heavy borrowers that do not engage in commensurate lending may be penalized. Multiple users that lend and borrow digital items from one another may be connected in a social network. The nature of a relationship in the social network may and the lending metrics of users are factors used to make lending decisions.

Abstract: Organizing collaborative annotations of digital items is described. In a particular embodiment, a server system receives a filter request from a client device to filter a plurality of annotations according to criteria included in the filter request. The plurality of annotations is stored at an annotations database coupled to the server system. The server system sends filter results to the client device based upon annotations matching the criteria of the filter request. The annotations may be filtered based on tags associated with respective annotations, where the tags categorize the respective annotations.

Abstract: Techniques for use with an electronic book reader include receiving localized evaluative feedback from users, pertaining to different locations within electronic content. The localized feedback is collected at a server and reported to content creators in reports that are formatted to indicate characteristics of the feedback at different locations within the electronic content.

Abstract: Digital items may be lent from one user to another. A lending system may facilitate matching users that have a digital item to lend with users that wish to borrow a digital item. Each user may have a reputation associated with his or her lending behavior that is represented as a lending metric. The lending metric may show whether a given user is primarily a lender or borrower of digital items. Heavy borrowers that do not engage in commensurate lending may be penalized. Multiple users that lend and borrow digital items from one another may be connected in a social network. The nature of a relationship in the social network may and the lending metrics of users are factors used to make lending decisions.

Abstract: A method for comparing content can include receiving first content generated by an author over a communications medium and comparing at least a portion of the first content to at least a portion of second content using one or more content-matching techniques to detect matched content. The method may further include providing content-matching feedback over the communications medium. The content-matching feedback can include suggestions for changing at least a portion of the first content based on the matched content. In some implementations, the first content can include a document written by the author, and the second content can include one or more publications.

Abstract: User content access events pertaining to a content item, such as an eBook, audio, video file, and so on, are collected and analyzed to determine progress data, including completion information about when the content item, or a portion thereof, has been completed. Once determined, further information or recommendations that have some relation to the completed content item may be presented to the user.

Abstract: Content items, such as e-books, audio files, video files, etc., may be recommended to a user based on the user's presence at a geolocation or venue. Geolocation is the geospatial location of the user, while a venue is a designated area for an activity, such as a concert hall, aircraft, waiting room, etc. The recommendations may be of content items relating to the geolocation or venue, or they may be content items being accessed by others who are, or have been, in approximately the same geolocation or venue.

Abstract: Architectures and techniques are described to provide customized versions of electronic books with various supplemental content items. The electronic books include a framework having core content that is provided with each electronic book and supplemental content portions that are populated with supplemental content items based on the preferences of particular readers of the electronic books. In some cases, the electronic books may include supplemental content options that are selectable to provide access to supplemental content items by readers of the electronic books. The supplemental content items accessible via the supplement content options may also depend on the preferences of the readers.

Abstract: In some implementations, a device displays supplemental information in connection with a digital work. The supplemental information may include a visual representation that represents one or more occurrences of an object in the digital work. The visual representation may include an area representative of an expanse of the digital work. At least one marking is located in the area in correlation to a location of an occurrence of the object in the digital work. In some examples, the visual representation may include a plurality of markings representing multiple occurrences of the object in the digital work, with a first or leftmost marking positioned in the area in proportion to a first occurrence of the object in the digital work. A second or rightmost marking may be positioned in the area in proportion to a final occurrence of the object in the digital work.