Physics is the most fundamental of the experimental sciences, as it seeks to explain the universe itself from the very smallest particles – currently accepted as quarks, which may be truly fundamental – to vast distances between galaxies. Classical physics, built upon the great pillars of Newtonian mechanics, electromagnetism and thermodynamics, went a long way in deepening our understating of the universe. Despite the exciting and extraordinary development of ideas throughout the history of physics, certain aspects have remained unchanged. Observations remain essential to the very core of physics, sometimes requiring a leap of imagination to decide what to look for, before models are developed to try to understand and explain these observations. Alongside the growth in our understanding of the natural world, perhaps the more obvious and relevant result of physics to most of our students is our ability to change the world. This is the technological side of physics, in which physical principles have been applied to construct and alter the material world to suit our needs, and have had a profound influence on the daily lives of all human beings. Physics is therefore a human activity, and students need to be aware of the process of physics in a context of dynamic change and places where physicists work.