47. A method for automatically mapping patterns of URLs of web pages on a website to one or more semantic types using a tag, the method, comprising: identifying a first web page and a second web page in the web site; retrieving a first URL of the first web page and a second URL of the second web page; storing the first and second URLs in memory for analysis; comparing URL segments in the first and second URLs and corresponding values in each field; extracting a first pattern by identifying a key field from the URL segments in the first URL; using the key field, identifying a first semantic type with which content embodied in the first web page has a first type of semantic relationship; storing the first pattern in a database embodied in a machine-readable storage medium as being mapped to the first semantic type; wherein, the tag has an associated weight value; and rating trustworthiness of the pattern extracted from the URL based on the associated weight value of the tag that is identified in the web page having the URL.
47. A method for automatically mapping patterns of URLs of web pages on a website to one or more semantic types using a tag, the method, comprising: identifying a first web page and a second web page in the web site; retrieving a first URL of the first web page and a second URL of the second web page; storing the first and second URLs in memory for analysis; comparing URL segments in the first and second URLs and corresponding values in each field; extracting a first pattern by identifying a key field from the URL segments in the first URL; using the key field, identifying a first semantic type with which content embodied in the first web page has a first type of semantic relationship; storing the first pattern in a database embodied in a machine-readable storage medium as being mapped to the first semantic type; wherein, the tag has an associated weight value; and rating trustworthiness of the pattern extracted from the URL based on the associated weight value of the tag that is identified in the web page having the URL. 51. The method of claim 47 , further comprising: using the first pattern, extracting a value from the key field of the URL segments in the second URL; identifying, based on the value in the key field, a second semantic type with which content embodied in the second web page has the first type of semantic relationship.