Computer networks are ubiquitous in modern life and are central to many aspects of society. Networks connect homes to essential utilities like electricity and water, and allow global communication through phones, email, and the internet. The internet is now ingrained in everyday life and many fields like education, business, and social interaction. Networks are also present in our bodies, minds, and the natural world. Modern life would not be possible without the vast interconnected computer and transportation networks that underpin the global economy.