8. A system of detecting an original document from a plurality of web documents, comprising: a processor in communication with a computer network and executing a plurality of processing components; the processing components including, a history information receiving component executed to receive history information for a uniform resource locator (URL) of each of web documents that are generated or modified in a web server at a time a notification is issued upon generation or modification of the web documents, the generation or modification of the web documents being detected by the web server when the web documents are cited as links in at least one web document in the web server; a collecting component executed to crawl the web documents corresponding to the received history information to determine whether the crawled web documents have been further modified since the time of receipt of the notification of generation or modification of the web documents, and to filter the crawled web documents by excluding each of the crawled web documents that are determined to be further modified since the time of receipt of the notification; and a detecting component executed to group the crawled web documents that are filtered by chunks of the crawled web documents, and detect an original document of the grouped documents based on the history information.
8. A system of detecting an original document from a plurality of web documents, comprising: a processor in communication with a computer network and executing a plurality of processing components; the processing components including, a history information receiving component executed to receive history information for a uniform resource locator (URL) of each of web documents that are generated or modified in a web server at a time a notification is issued upon generation or modification of the web documents, the generation or modification of the web documents being detected by the web server when the web documents are cited as links in at least one web document in the web server; a collecting component executed to crawl the web documents corresponding to the received history information to determine whether the crawled web documents have been further modified since the time of receipt of the notification of generation or modification of the web documents, and to filter the crawled web documents by excluding each of the crawled web documents that are determined to be further modified since the time of receipt of the notification; and a detecting component executed to group the crawled web documents that are filtered by chunks of the crawled web documents, and detect an original document of the grouped documents based on the history information. 9. The system of claim 8 , wherein the notification is generated by a pingback protocol when the web documents are generated or modified.