Rename

Rename File

Delete :

deleting character that's match to every filename in a folder.

if you have:

file-01.pdf  
file-02.pdf  
file-03.pdf  

fill the delete input field with file, then you will have result as follows:

-01.pdf  
-02.pdf  
-03.pdf  

Replace :

replace character to any character you want to replace. if you have:

file-01.pdf  
file-02.pdf  
file-03.pdf  

fill the from input field with file, and to with goodbooks, then you will have result as follows:

goodbooks-01.pdf  
goodbooks-02.pdf  
goodbooks-03.pdf  

Insert :

insert character to the beginning(prefix) and/or the end(suffix) of your filename.
if you have:

file-01.pdf  
file-02.pdf  
file-03.pdf  

fill the before input field with library-,
and after with collection, then you will have result as follows:

library-file-01 collection.pdf  
library-file-02 collection.pdf    
library-file-03 collection.pdf