Read an exclusive excerpt from Nuts & Bolts by Roma Agrawal

I must have been about five years old, and was living with my parents and sister in snowy upstate New York. Whether it’s the matter that makes our universe, living biological creatures, or the human-made objects we invented, complex compositions are made up of smaller and simpler, well, things. Inside all the humanmade things around us are fundamental building blocks without which our complex machinery wouldn’t exist. Each of the seven objects I’ve selected – the nail, the wheel, the spring, the magnet, the lens, string and the pump – are wonders of design that went through many different iterations and forms. While we think of engineering as a field littered with inanimate objects and complex pieces of technology that often feel alien or beyond our understanding, at the heart of engineering is people: those who create it, those who need and use it, those who sometimes inadvertently make a contribution to it.