To understand the implications of license plate readers, both the benefits and the potential for misuse, it helps to understand the technology. The data for these programs is generated by Automatic License Plate Recognition (ALPR), a technology that uses cameras and software to find and record license plate numbers. The cameras usually operate on both the infrared and visual light spectrums, allowing the system to work during day and night. A processing unit takes the image recorded by the camera, and using algorithms isolates the numbers from visual noise. The plate numbers are then stored, timestamped, and tagged with a location.