Signal strength refers to the measure of how well a device, like a smartphone or a Wi-Fi router, can receive and transmit signals. It is usually represented in decibels (dB) and indicates the quality of the connection. A stronger signal means better performance, allowing for faster internet speeds and clearer calls. When you are far away from a Wi-Fi router or in a crowded area, the signal strength may decrease, leading to slower connections or dropped calls. Factors like walls, distance, and interference from other devices can affect signal strength, making it important to find the best location for your devices.