Hi,
I want to replace the content in 3rd column in the first file by the line in the 2nd file (a list) if matches with 1st column of 2nd file. There are many 1st files in different directories:

File1

172.27.1.15 222 I_J_Mar_Sci_34_27.pdf
172.27.28.1 489 Sci_Cult_71_60.pdf
172.27.12.5 98 chap7_ref.pdf
172.27.1.73 98 chap7_ref.pdf

File2

chap7_ref.pdf NAP
chap1.pdf NAP
I_J_Mar_Sci_34_27.pdf NACP
Sci_Cult_71_60.pdf OAP
Human.pdf NAP

Required Output

172.27.1.15 222 I_J_Mar_Sci_34_27.pdf NACP
172.27.28.1 489 Sci_Cult_71_60.pdf OAP
172.27.12.5 98 chap7_ref.pdf NAP
172.27.1.73 98 chap7_ref.pdf NAP

Is it possible to solve the problem with shell script or Perl script and what will be the code?

awk '
NR==FNR{a[$1]=$2;next}
a[$3]{$0=$0" "a[$3]}1
' file2 file1

Thanks for your reply.
I have little doubt.....If in the File1 the 3rd coumn and 2nd column interchanged then where I need to change in code.

Thanks for your code. I could able to my required task. I also could able to do the task in files where the columns inter change