Compare Suite 

Compare Suite can compare both - related and non-related files. "By keywords" comparison feature highlights common and unique keywords, allowing to compare non-related files. Word-by-word comparison compares files with a common ancestor.
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AJC Diff 

This program compares two files. Files can be shown combined or side by side. Full diff, context diff or differences only. Color coding, line nos, search and print options.
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Compare PDF 

Compare PDF can compare both - related and non-related Adobe Acrobat files. "By keywords" comparison feature highlights common and unique keywords, allowing to compare non-related files. Word-by-word comparison compares files with a common ancestor
compare pdf pdf compare compare adobe acrobat by keywords folder comparison merge text comparison report compare folder