Other business people seem to believe a myth that there is a "standard" NDA, or, put somewhat differently, that all NDAs are the same. There is no "standard" NDA and NDA forms often vary in important ways.
I recently wrote an article that was published in Bloomberg's Corporate Counselor newsletter regarding the basics of NDAs. Due to our agreement with the publisher, I cannot post it directly here, but it can be accessed through the "publications" banner on the right side my bio on the Barnes & Thornburg website here. It may take a few clicks, but it will be worth it!