Networking forms the foundation of modern computing, enabling devices to communicate and share resources across local and global infrastructures. From the seven-layer OSI model to protocols managing everything from IP addressing to data encryption, networking encompasses both physical transmission media and logical routing decisions. Understanding networking means grasping how packets traverse routers, switches, and firewalls—and recognizing that even a single misconfigured subnet mask or firewall rule can cascade into widespread connectivity failures or security breaches.