What is Redaction?

I was browsing through Michael Barr's post about the unintended acceleration problem in Toyota cars. He uses the term redaction/redacted at a number of places. It is a word that I had never come across. He explains the term in the second paragraph of his post but since I wanted to get to the details of likely defects in Toyota's software, I missed it. A Google look up led me to believe it meant a frame or a side-bar that one commonly finds in article and books. (Incidentally Hindu's series on WikiLeaks concerning India also mentions redaction by the Indian Embassy of the Indian Ambassador's statement.)

I downloaded Appendix A  to NASA's  report from NHTSA's site. When first I saw the document on the screen I thought there was some problem with my internet connection. It took me a couple of seconds to realize that those black boxes were redaction - plain and simple censoring. To me that appears very suspicious.

I have browsed through the post mentioned above and the subsequent post. Both posts deserve study. I strongly urge all those concerned with quality of large embedded software to study the posts.