It would help if you told everyone what you were trying to get done. Can't pick the right tool for the right job if you don't know what the job is. For current threads on the subject, try typing "encrypting" in the search box for the site.

I would also recommend picking up Bruce Schneier's masterpiece on the subject: Applied Cryptography. This is not a subject that you want to get into without doing a lot of homework.

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