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For "File Shredder", look under the Finder menu for "Secure Empty Trash". You can enter Secure Empty Trash into the Help menu in Finder and get more info. You can also google the search terms Secure Empty Trash.

If you mean something else by "File Shredder", please explain what you want the program to do.
 
What are the best programmes for these tasks please?
As chown33 said, using Secure Empty Trash should suffice for securely deleting files. As for "obliterate browsing", I'm assuming you mean erasing your browsing history. If so, you can do that with Safari. There's no need for a 3rd party app.
 
For....

file shredding I have a long time using PGP Desktop in the respective versions for Mac and Windows. Obliterate browsing? I suppose that depends in what browser you use. But can be done without special software....

:):apple:
 
Thanks for these last two suggestions, I am a bit undecided now, with several options. I will have to consider them all once looked at if that is possible without downloading them.
 
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