Hacking is not a new practice, as long as people had to make do, had to get things done, had to find a quick fix or a new solution, hacking was around. It is commonly seen as a bottom-up, grass root approach to technology, and therefore sometimes associated with an aura of rebellion and democratizing decentralization. Yet, most of our products are not produced by highly sophisticated robots, but by people working hands-on, hacking away under quite harmful conditions, yet with ridiculously small income. And because they don’t own the patent of what they are manufacturing, those who do own the patent get the main portion of the money we pay for these products. Nevertheless, communities who still share skills on how to produce, manufacture, hack and repair things, even if out of necessity, enjoy a certain form of autonomy and seem to have the longer breath. Communities who hack, come up with new ideas they want to tell others, voluntarily or involuntarily they collaborate and mingle. This also counts for people who might be seen as privileged, because they are artists, culture workers or designers. They seem to have made the choice to live in a precarious situation for the sake of self-realization. I think many of them haven’t consciously made that choice, but they do capitalize on the positive effects of hacking too, the sharing platforms, the never ending pool of ideas, the feeling of autonomy, the long breath. Many artists hack and share their new ideas in workshops. Workshops in which people hack together, try out different circuits and practices, concepts and new variations of concepts. It has developed into a unique and ubiquitous format, that can create a satisfying experience. For a variety of reasons, as you can read in the interviews with artists featured in this book. However, learning about hacking practices is not only a way to get knowledgable about how stuff is made, but to cultivate creativity, out of the box thinking, personal expression. Specially in schools it can encourage kids to become inventive and resourceful, gain self-esteem, find something they are passionate about. Most of all it de-mythifies science and technology and makes it something you can do everywhere and fearlessly, self-driven, no matter what others might think. The alienation most of us feel, when they purchase all their goods (from nutrition to furniture to electronic devices) off the shelf in some shop has been discussed by many theorists. This alienation has been identified as the cause of countless problems in industrialized countries. If you try out the illustrated instructions with a group of friends or colleagues, neighbors or kids, maybe you will get seduced to do more, to make more things by yourself and to find your own way to create technology. This is why we start to share circuits with this book, start to frame them as artistic practice, that specific people and artists came up with or use in their work. With every instruction comes a short bio of the person who introduces it. If you try something and it does not function immediately, don’t get frustrated, let some one else have an eye on it, a pair of fresh eyes can find the bug faster than you think. If we made a mistake in our instructions, please feel free to contact us. After all we love the idea of open source, because it guarantees fast, collective debugging. Now just a few words to the individual instructions. They are in an intentional order, starting with a simple lemon battery, for people who want to do this from scratch. It offers definitions of electricity and the units volt and ampere and how to use a multimeter. Tutorials on lemon batteries are easy to find online, in case something is not described clear enough in this book. The following instructions are becoming a little more challenging. We added more tools and materials, so that you can build upon the knowledge you gained in the previous instruction. As you will see, we put some emphasis on how to generate electricity with the first two instructions. The third instruction is introducing the use of LEDs and how to make a switch, but without the need to solder. Since many of you would love to try how to solder, we added a short introduction to soldering to the last instruction, which you can instantly apply in order to make a tiny and simple megaphone. Just beware of inhaling the fume coming from the soldering iron, when you are pregnant. We hope that you will be able to find all the required materials and electronic parts in local shops or by opening old and broken devices. You can salvage loudspeakers for your circuit by, for example, opening the casing of broken computer speakers. You can re-use LEDs that you find in old toys, for example little toy dogs with blinking eyes or broken musical instruments for kids. For the lemon batteries you can take the almost rotten lemon you have got left in your fridge. We would just not recommend to eat fruits or vegetables anymore, after you experimented with them. Now we hope that you are curios enough to get started and that you will enjoy the wonderous experience of becoming a real hardware hacker!