Hierarchical document comparison system and method

A document comparison system designed to compare at least two very large and very similar documents to quickly locate and identify differences in the documents, wherein the documents include a first document and a second document each having a large number of segments, each segment having a label and including a plurality of characters, said document comparison system comprising:

• a computer, said computer comprising a module executable in said computer wherein said module is configured to receive a request to compare the first document and the second document, said module performs a character-by-character comparison of at least some of the characters of the first document to at least some of the characters of the second document and determines whether there are differences between the first document and the second document, said module listing only the labels, and no other content, of only those segments that contain at least one difference in a first display in which the listed segment labels from the first document appear in a first display portion of said first display and the listed segment labels from the second document appear in a second display portion of said first display;
• wherein said module is further configured to receive a request to display at least one difference between (a) at least one segment of the first document having a segment label listed in said first display portion of said first display and (b) at least one corresponding segment of the:
• second document having a segment label listed in said second display portion of said first display, said module displaying the characters of the at least one segment of the first document and the characters of the at least one corresponding segment of the second document in a second display in which at least some of the characters of the at least one segment of the first document appear in a first display portion of said second display and at least some of the characters of the at least one corresponding segment of the second document appear in a second display portion of said second display, wherein the characters which are different are distinguished in said second display.

A method of comparing at least two very large and very similar documents to quickly locate and identify differences in the documents, wherein the documents include a first document and a second document each having a large number of segments, each segment having a label and including a plurality of characters, said method comprising:

• receiving a request to compare the first document and the second document;
• performing a character-by-character comparison of at least some of the characters of the first document to at least some of the characters of the second document;
• determining whether there are differences between the first document and the second document;
• listing only the labels, and no other content, of only those segments that contain at least one difference in a first display in which the listed segment labels from the first document appear in a first display portion of said first display and the listed segment labels from the second document appear in a second display portion of said first display;
• receiving a request to display at least one difference between (a) at least one segment of the first document having a segment label listed in said first display portion of said first display and (b) at least one corresponding segment of the second document having a segment label listed in said second display portion of said first display;
• displaying the characters of the at least one segment of the first document and the characters of the at least one corresponding segment of the second document in a second display in which at least some of the characters of the at least one segment of the first document appear in a first display portion of said second display and at least some of the characters of the at least one corresponding segment of the second document appear in a second display portion of said second display;
• and
• distinguishing the characters which are different in said second display;
• wherein each of said segment labels is unique within one of said first document and said second document.

A document comparison system designed to compare at least two very large and very similar documents to quickly locate and identify differences in the documents, wherein the documents include a first document and a second document each having a large number of segments, each segment having a label and including a plurality of characters, said document comparison system comprising:

• a computer, said computer comprising a module executable in said computer wherein said module is configured to receive a request to compare the first document and the second document, said module performs a character-by-character comparison of at least some of the characters of the first document to at least some of the characters of the second document and determines whether there are differences between the first document and the second document, said module listing only the labels, and no other content, of only those segments that contain at least one difference in a first display in which the listed segment labels from the first document appear in a first display portion of said first display and the listed segment labels from the second document appear in a second display portion of said first display;
• wherein said module is further configured to receive a request to display at least one difference between (a) at least one segment of the first document having a segment label listed in said first display portion of said first display and (b) at least one corresponding segment of the second document having a segment label listed in said second display portion of said first display, said module displaying the characters of the at least one segment of the first document and the characters of the at least one corresponding segment of the second document in a second display in which at least some of the characters of the at least one segment of the first document appear in a first display portion of said second display and at least some of the characters of the at least one corresponding segment of the second document appear in a second display portion of said second display, wherein the characters which are different are distinguished in said second display;
• wherein each of said segment labels is unique within one of said first document and said second document.