9. Computer information navigation apparatus, comprising: in a computer memory: (i) a first source of information; and (ii) one or more second sources of information, information from each second source having a parent-child relationship with the first source information, the first source information being parent information; in a processor coupled for communication with the computer memory, a keyword engine executed by the processor and responsive to the first and second sources of information, the keyword engine extracting keywords from the first source information and from each of the second sources information in a manner such that, for each extracted keyword, the keyword is related to the first source information and at least one second source information, the keyword engine producing respective groupings of second source information related by keyword and resulting in precise keywords that enhance retrieval of second sources of information; wherein the keyword engine extracting keywords utilizes a semantic lexicon tool, and includes: extracting initial keywords from the first source; forming an initial taxonomy from the extracted initial keywords; detecting in the second sources words that match the initial taxonomy but that do not duplicate the extracted initial keywords of the first source; and combining the extracted initial keywords from the first source and the detected words from the second sources, said combining forming the listing of keywords; and an output member coupled to the keyword engine to receive the extracted keywords, the output member executed by a computer and displaying to a user a listing of the received keywords in a manner enabling the user to navigate the one or more second sources of information, different keywords in the displayed listing referencing the different respective groupings of second source information and the different respective sets of second sources having subject matter of the first source of information shown to the user.
9. Computer information navigation apparatus, comprising: in a computer memory: (i) a first source of information; and (ii) one or more second sources of information, information from each second source having a parent-child relationship with the first source information, the first source information being parent information; in a processor coupled for communication with the computer memory, a keyword engine executed by the processor and responsive to the first and second sources of information, the keyword engine extracting keywords from the first source information and from each of the second sources information in a manner such that, for each extracted keyword, the keyword is related to the first source information and at least one second source information, the keyword engine producing respective groupings of second source information related by keyword and resulting in precise keywords that enhance retrieval of second sources of information; wherein the keyword engine extracting keywords utilizes a semantic lexicon tool, and includes: extracting initial keywords from the first source; forming an initial taxonomy from the extracted initial keywords; detecting in the second sources words that match the initial taxonomy but that do not duplicate the extracted initial keywords of the first source; and combining the extracted initial keywords from the first source and the detected words from the second sources, said combining forming the listing of keywords; and an output member coupled to the keyword engine to receive the extracted keywords, the output member executed by a computer and displaying to a user a listing of the received keywords in a manner enabling the user to navigate the one or more second sources of information, different keywords in the displayed listing referencing the different respective groupings of second source information and the different respective sets of second sources having subject matter of the first source of information shown to the user. 13. Apparatus as claimed in claim 9 wherein the displayed listing is any of a tag cloud, a taxonomy, and an ordered list.