Hello,
    I have a problem with comparision of two word documents.For example,i have two files one is original and second is some modifitions in first file.How to compare these two documents and pick up those modifications are done in second file?

I'm not using a US version of Office so the items are a little uncertain.

Open one of the docs,
in the Functions menu choose Merge and Compare or anything that resembles this,
choose the file to be compared against,
in the bottom right you should be able to choose something like 'Compare only'
Press OK and a new document should show the differences.

Before you do all this, start the macroeditor to get the code.