This is an introduction to cryptography for developers. It assumes that you aren't looking for cryptographic theories, but practical ways to use cryptography in your projects. It covers the basic standard building blocks, and includes some sample code to help you get started. Right now, it's pretty short but I'm open for topics to discuss.
This document is a published version of the original blog post. You can read the post in its entirety there; this is primarily offered as way to support the author and to make it easier to publish in multiple ebook formats.