1. An image display apparatus for selecting an arbitrary image sensing device from one or more image sensing devices connected, and displaying a video obtained from the selected image sensing device, comprising: first memory for holding management data which contains at least a name, identification number, and connection information of each image sensing device, and is described in a data description language; second memory for holding a display style of the management data, which is described in a style designation language; and data description means for describing management data in the data description language, and storing the data in said first memory.