A wireless network is essential for connecting devices to the Internet, and the primary device for this connection is a wireless router or access point. This device broadcasts the internet signal via Wi-Fi, allowing devices such as laptops, smartphones, and tablets to connect wirelessly. Wireless routers also manage traffic between connected devices and can provide additional features, such as security measures and network management. Without a wireless router, access to the internet on mobile devices would be limited to wired connections only.