To provide a display device facilitating display of desired images on display sections under environment connected to external devices of cameras, or the like, and to provide a display system and a program for display.

When the connection of an external device, such as a DSC 200, to the display device 100 is detected, management information on management of images is acquired from the DSC 200 at that time for storing in a management DB 105b, thus uniformly managing updated management information for management of images by the display device 100 including an external device, such as the DSC 200. In the case of an instruction to display a desired image designated by the management information, the image is acquired from an own image memory 105a, a storage medium 209, or the like in the DSC 200 for displaying on the display section 109.