FLIR and thermal imaging both refer to the process of capturing images using infrared radiation, however there are some key differences between them. FLIR stands for “Forward Looking Infrared” and is a type of active thermal imaging that uses an external light source to illuminate objects or areas. This produces higher-resolution images with greater detail than traditional passive thermal imaging which relies solely on body heat from its subjects. Additionally, FLIR sensors can detect changes in temperature over time, providing more information about the environment than just one single image captured by a passive system alone.