A wireless router is a device that connects to the internet and allows multiple devices, such as computers, smartphones, and tablets, to access the internet without physical cables. It uses radio waves to transmit data, creating a local network that enables devices to communicate with each other and share resources like printers. Wireless routers often come with built-in security features to protect the network from unauthorized access. They can also include additional functionalities, such as firewalls and Quality of Service (QoS) settings, which help manage internet traffic and prioritize certain applications for better performance.