This section will give you a basic overview of physical computing systems. Physical computing systems are electronic systems that use software and hardware together to get input from the physical world using the hardware and respond to it by providing an output based on the software running on the hardware. These systems are also called embedded systems in different applications. In general terms, any system that interacts with the analog world using hardware sensors and senses the input obtained and responds accordingly based on the software programmed for it is called a physical computing system.

Right from your music player, washing machine, automatic door opener, and mobile phone, everything that takes input from the physical world using sensors and buttons and responds to it by making a change in the physical world with its output is a physical computing system.

Take, for example, your washing machine. Based on the input you provide by clicking...