The Arduino is an open source electronics platform that has gained a huge following amongst hobby electronic enthusiasts.
This book is by Massimo Bani who is co-founder of Arduino platform. The book is aimed at the complete beginner to both electronics as well as the Arduino assuming no former electronics or programming experience.
The book takes an informal approach using hand drawn pictures for the circuit diagrams and board layouts and takes a gentle approach to introducing the subject. It uses a teach by tinkering approach encouraging readers to have a go at sticking components together and seeing what happens. This can be a good way to learn as it helps to keep interest, but it has it’s limitations and a more formal understanding of electronics is going to be needed to go beyond very basic sensor and output circuits.
The examples use a breadboard (solder-less prototyping board) so you don’t have to be able to solder, and the programming of the Arduino is basic and explained for the non-programmer.
The most complex circuit is a light that changes colour based on certain words on a website. This sounds ground, but the electronics is just a few LEDs and the most useful aspect of this is the serial communications between processing language running on the computer and the Arduino.
The appendix includes a list of the programming commands that can be used with the Arduino which is quite useful.
If you are completely new to electronics then this is a cheap book that starts from the very beginning. If however you already have a basic understanding of electronics (eg. GCSC physics) then you may be better of looking for a book that goes a bit further than Getting Started with Arduino.