What does it look like?
Here are some pictures of routers from a variety of manufacturers. The key feature is one or more antennas.
Unplug the router!
What will happen?
Most routers have a small wall power supply that is plugged into a standard wall outlet. It looks a lot like the one you've used for a cell phone. When you unplug the power supply, the router and Wi-Fi will be powered down. This will result in the loss of connection to the Internet for all of your devices that rely on a router. Most cell phones will automatically switch over to the data plan of your cell phone service. But sure to pay attention to your use of social media and web browsing to avoid higher than normal charges for data usage.