Ask HN: What do you want to see in a manual for SSL/TLS/HTTPS?

I am writing a short manual on SSL/TLS/HTTPS/Cryptography and i am wanting to know what people would like to see in such an ebook. I want to think of it as a "missing manual" that you could hand to someone to quickly read up on the subject and have all the basic knowledge needed to join discussions in the field. Or to start a course that touches on the subject and required basic knowledge. By short i mean about 20,000 to 25,000 words.