A display apparatus comprising: a substrate; a display unit on the substrate and comprising: a display region comprising: a first display region having therein a plurality of first pixel circuits, and a plurality of first light-emitting devices (OLED1) configured to be driven by the plurality of first pixel circuits; and a second display region having therein a plurality of second pixel circuits, and a plurality of second light-emitting devices (OLED2) configured to be driven by the plurality of second pixel circuits; a plurality of scan lines crossing the display region in a first direction; and a plurality of data lines crossing the display region in a second direction that is different from the first direction wherein the data lines crossing the second display region are extensions of data lines crossing the first display region, wherein the number of the first light-emitting device (OLED1) per unit area is equal to the number of the second light-emitting devices (OLED2) per unit area wherein the total number of the first light-emitting devices (OLED1) driven by one of the first pixel circuits is less than the total number of the second light-emitting devices (OLED2) driven by one of the second pixel circuits so that the resolutions of the first and second display regions (DA1, DA2) are different, and wherein the display unit and the substrate collectively define at least one through portion in the second display region. a substrate; a display unit on the substrate and comprising: a display region comprising: a first display region having therein a plurality of first pixel circuits, and a plurality of first light-emitting devices (OLED1) configured to be driven by the plurality of first pixel circuits; and a second display region having therein a plurality of second pixel circuits, and a plurality of second light-emitting devices (OLED2) configured to be driven by the plurality of second pixel circuits; a plurality of scan lines crossing the display region in a first direction; and a plurality of data lines crossing the display region in a second direction that is different from the first direction wherein the data lines crossing the second display region are extensions of data lines crossing the first display region, a display region comprising: a first display region having therein a plurality of first pixel circuits, and a plurality of first light-emitting devices (OLED1) configured to be driven by the plurality of first pixel circuits; and a second display region having therein a plurality of second pixel circuits, and a plurality of second light-emitting devices (OLED2) configured to be driven by the plurality of second pixel circuits; a first display region having therein a plurality of first pixel circuits, and a plurality of first light-emitting devices (OLED1) configured to be driven by the plurality of first pixel circuits; and a second display region having therein a plurality of second pixel circuits, and a plurality of second light-emitting devices (OLED2) configured to be driven by the plurality of second pixel circuits; a plurality of scan lines crossing the display region in a first direction; and a plurality of data lines crossing the display region in a second direction that is different from the first direction wherein the data lines crossing the second display region are extensions of data lines crossing the first display region, wherein the number of the first light-emitting device (OLED1) per unit area is equal to the number of the second light-emitting devices (OLED2) per unit area wherein the total number of the first light-emitting devices (OLED1) driven by one of the first pixel circuits is less than the total number of the second light-emitting devices (OLED2) driven by one of the second pixel circuits so that the resolutions of the first and second display regions (DA1, DA2) are different, and wherein the display unit and the substrate collectively define at least one through portion in the second display region.