HDR stands for “high dynamic range”. It merges pictures of different exposures to have the “perfect exposure” all around. HDR photography is seen mostly with highly saturated landscapes and fantastic clouds. To get this effect, a photographer must use a tripod and shoot whatever they are shooting with five different exposures in the same position. One with normal exposure, one with one and two stops down and one with one and two stops up. Then you use a photo editing app that can merge photographs together. Now, HDR photos are not only restricted to landscapes and fantastic clouds but can be of a city. But if you shot a landscape and there were no clouds, get clouds from the internet and blend them into the photograph. That is HDR.