Why my book can be downloaded for free by Mark Dominus.
From the post:
People are frequently surprised that my book, Higher-Order Perl, is available as a free download from my web site. They ask if it spoiled my sales, or if it was hard to convince the publisher. No and no.
I sent the HOP proposal to five publishers, expecting that two or three would turn it down, and that I would pick from the remaining two or three, but somewhat to my dismay, all five offered to publish it, and I had to decide who.
One of the five publishers was Morgan Kaufmann. I had never heard of Morgan Kaufmann, but one day around 2002 I was reading the web site of Philip Greenspun. Greenspun was incredibly grouchy. He found fault with everything. But he had nothing but praise for Morgan Kaufmann. I thought that if Morgan Kaufmann had pleased Greenspun, who was nearly impossible to please, then they must be really good, so I sent them the proposal. (They eventually published the book, and did a superb job; I have never regretted choosing them.)
But not only Morgan Kaufmann but four other publishers had offered to publish the book. So I asked a number of people for advice. I happened to be in London one week and Greenspun was giving a talk there, which I went to see. After the talk I introduced myself and asked for his advice about picking the publisher.
Access to “free” electronic versions is on its way to becoming a norm, at least with some computer science publishers. Cambridge University Press, CUP, with Data Mining and Analysis: Fundamental Concepts and Algorithms and Basic Category Theory comes to mind.
Other publishers with similar policies? Yes, I know there are CS publishers who want to make free with content of others, not so much with their own. Not the same thing.
I first saw this in a tweet by Julia Evans.