Highlighting notebooked web content

A system comprising:

• one or more computers configured to perform operations comprising:
• receiving, in a system that maintains web notebooks for a plurality of user accounts, a request for a web document from a client computing device that is associated with a particular user account of the plurality of user accounts;
• determining a number of web notebooks that each include a portion of the web document, the number of web notebooks being associated with the plurality of user accounts;
• determining a threshold number, the threshold number being greater than one, wherein determining the threshold number comprises:
• determining a subject matter of the requested web document, wherein the subject matter is based on at least one of a subject and a category of information provided in the requested web document;
• determining a popularity of the subject matter, wherein the determining comprises analyzing the web notebooks to identify instances of content associated with the subject matter having been added to one or more of the web notebooks;
• and
• setting the threshold number, wherein the threshold number is proportional to the determined popularity of the subject matter;
• and
• determining that the number of web notebooks meets or exceeds the threshold number, and in response:
• providing for display by the client computing device a highlighted version of the web document, wherein the highlighted version comprises the web document and a visual indicator that highlights the portion, and
• providing access to one or more of the number of web notebooks in association with the highlighted version of the web document.

A non-transitory computer readable medium storing instructions that, when executed by one or more processors, cause the one or more processors to perform operations comprising:

• receiving, in a system that maintains web notebooks for a plurality of user accounts, a request for a web document from a client computing device that is associated with a particular user account of the plurality of user accounts;
• determining a number of web notebooks that each include a portion of the web document, the number of web notebooks being associated with the plurality of user accounts;
• determining a threshold number, the threshold number being greater than one, wherein determining the threshold number comprises:
• determining a subject matter of the requested web document, wherein the subject matter is based on at least one of a subject and a category of information provided in the requested web document;
• determining a popularity of the subject matter, wherein the determining comprises analyzing the web notebooks to identify instances of content associated with the subject matter having been added to one or more of the web notebooks;
• and
• setting the threshold number, wherein the threshold number is proportional to the determined popularity of the subject matter;
• and
• determining that the number of web notebooks meets or exceeds the threshold number, and in response:
• providing for display by the client computing device a highlighted version of the web document, wherein the highlighted version comprises the web document and a visual indicator that highlights the portion, and
• providing access to one or more of the number of web notebooks in association with the highlighted version of the web document.