I found some bit of introduction at the book's link in Amazon,
If you did have some bit of experience with HTML, CSS, and JavaScript
you should be good i hope.
So here goes the introduction about the book.......
NW.js and Electron are desktop application frameworks powered by Node.js. They allow developers to create cross-platform desktop apps using HTML, CSS, and Java-Script. They offer web designers and developers a way to take their existing skills for crafting web apps and interfaces, and apply that to building desktop apps. The frameworks also support shipping apps for Mac OS, Windows, and Linux from the same codebase, meaning that developers can save time and energy when creating desktop apps that all OSs can use.........