If you want to compare two different text files, then manually it can become a stressful job because you wont be able to make the right comparision by just looking at both the files. Here comes a tool which is called as ExamDiff useful for visual file comparison in any windows based operating system. You just need to download both the files on your computer and import them into the ExamDiff Application.
This kind of tool is useful when you want to compare two files, when they are available as different versions. Select both the files one by one and it will show you a two tabbed display with all the compared text in the form of added, deleted & changed text. This way you can find what all updations have been made to the original file.
You dont have to buy this tool because you are offered with a full featured 30days version. Here are some more features of this software.