A DisplayPort to HDMI adapter allows you to connect a device with a DisplayPort output (like a computer or laptop) to a display with an HDMI input (like a monitor or TV). It essentially converts the digital DisplayPort signal to an HDMI signal, enabling you to view the display output on the connected HDMI device. These adapters are typically unidirectional, meaning they only convert from DisplayPort to HDMI, not the other way around.