WD My Book authorization: only reading on Mac OS X

For using my book external hard disk on my macbook pro, it’s requires formatting for Mac OS X. Right now, the authority is set to ‘only reading’. I want to be able to do thing with it as wel…

Do I need software for formatting? And how do I do it?

If the drive came formattted for Windows NTFS it is read only on a Mac. You will need to reformat it for the Mac or find software that will let you write on the drive as is. Reformatting will wipe out all data on it now.