This question is bothering me, my dm couldn't answer it. What is the difference between a spell scroll and a page of spellbook? One goes "puff" after use while others stays permanently. Also I'm curious about this puff effect, something like the content vanishes or paper burns up?
A spellbook contains the formula for a spell. A scroll contains an almost-completed casting of a spell - the equivalent of what you would prepare for the day, in written form - just speak the completion of the spell to activate it. When you complete the spell inscribed on a scroll, the contents of the scroll are erased, just as the spell is erased from your mind, when you cast it.
@RMorrisey's answer is excellent, I'll just paraphrase it. The spell scroll is like a completed webpage whose address you type into your browser, hit enter and there you go, the website comes up. The spell book is more like a handbook on webdesign and web programming (how to design and prepare visuals for the site, write HTML, CSS, JS and so on, the higher level the spell the more components for your site) that lets you learn how to build websites. :)
Fundamentally, a scroll is a magic item, designed to trigger when read properly. It holds the spell, and a matrix for triggering its release and aiming it. It can hold a spell indefinitely.
A Spellbook page is a different kind of magic item - much weaker - and is able to short-term hold patterns for spells which the mage "binds" to himself after shaping in the page, to be cast with a component or 3 (V, S, &/or M). The caster needs to be attaching the spell in its prepared state to himself within minutes, or the spell is lost.
Now, in some D&D editions, a spellbook page can also be used as a scroll; in such cases, the energy seems to be drawn from the page and the enchantments which make it a spellbook page and not just words on a page.
The game mechanical difference is that with a scroll you do not need to use a spell slot. The creator empowered the scroll and it is that charge, you use up part of the casting, destroys the scroll. It is a bit like the difference between be given a DVD with a program on (a spell book) and a computer with a halted program (a scroll). Once you have restarted the program (cast the spell on the scroll) it runs it course and is gone from memory and you have used up the battery. You could copy the memory of the halted program from memory to a DVD but that uses up the charge as well. To run it you need another one charge computer (ie a spell slot) to load and run it from your DVD. You can think of a spell book as like a library of DVDs each with a program on a page. You have so many computers that can run these small computers but they only have charge for one spell and then need a day in the sun to recharge. Rubbish analogy, I know, but it works for me ;)