9. The method of claim 1 , where presenting the comment in connection with the one of the one or more second documents includes: receiving a request from the client device, where the request includes information identifying the one of the one or more second documents, identifying, based on the request, the comment in the memory, and determining whether to present the comment or a manner in which to present the comment in connection with the one of the one or more second documents.
1. A method performed by one or more server devices, the method comprising: receiving, by a processor associated with the one or more server devices, a comment associated with a first document, the comment providing an opinion of, or remarks upon, a content of the first document; obtaining, by a processor associated with the one or more server devices, document clustering information which indicates that the first document is clustered with one or more second documents, the document clustering information being based on: textual information included in the first document, and textual information included in the one or more second documents; storing, in a memory associated with the one or more server devices, the comment in association with the first document and the one or more second documents based on the document clustering information indicating that the first document is clustered with the one or more second documents; presenting, by the one or more server devices, the comment in connection with the first document when the first document is accessed by a client device; and presenting, by the one or more server devices, the comment in connection with one of the one or more second documents when the one of the one or more second documents is accessed by the client device.