What device converts a wired network into a wireless network?

The device that converts a wired network into a wireless network is an access point. An access point serves as a bridge that allows wireless devices to connect to a wired network, enabling devices such as laptops, smartphones, and tablets to access the network without requiring physical cables. This functionality is essential for providing flexibility and mobility within a network.

In contrast, a switch operates within a wired environment, connecting multiple devices to create a local area network (LAN) but does not have the capability to handle wireless connections. A modem is designed to convert digital signals to analog for transmission over phone lines or cable systems, and it primarily connects to the internet rather than managing network traffic. A router, while it can route traffic between different networks and often has built-in wireless capabilities, it is not solely designed for converting wired networks to wireless; it primarily manages the distribution of data between devices on a network. Therefore, among the options provided, the access point is specifically tailored for creating wireless connectivity from a wired infrastructure.