A display device comprising: a voice recognition unit configured to receive (S311) a voice command; a wireless communication unit ; a storage unit ; a control unit configured to acquire (S313) a function corresponding to the voice command; a determination module configured to determine a provider providing the function based on a first condition, the provider being at least one of a first external server , a second external server and the display device; an output unit configured to output (S337) the result of executing the function and a keyword determination unit configured to recognize (S315) a preset keyword in the received voice command, wherein the control unit is configured to determine (S317) a provider providing the function based on the recognized keyword when the keyword determination unit recognizes the preset keyword, the provider being at least one of the first external server, the second external server and the display device; wherein the control unit is further configured to receive data related to the function from at least one of the first external server (S325), the second external server (S333) and the storage unit of the display device (S335) according to the determined provider, and to execute the function based on the received data, whereby, when the provider determined by the control unit based on the recognized keyword is the first external server (S319, YES) or the second external server (S327, YES): the control unit is configured to execute the data related to the function only when the provider determined by the control unit based on the recognized keyword matches the provider determined by the determination module. a voice recognition unit configured to receive (S311) a voice command; a wireless communication unit ; a storage unit ; a control unit configured to acquire (S313) a function corresponding to the voice command; a determination module configured to determine a provider providing the function based on a first condition, the provider being at least one of a first external server , a second external server and the display device; an output unit configured to output (S337) the result of executing the function and a keyword determination unit configured to recognize (S315) a preset keyword in the received voice command, wherein the control unit is configured to determine (S317) a provider providing the function based on the recognized keyword when the keyword determination unit recognizes the preset keyword, the provider being at least one of the first external server, the second external server and the display device; wherein the control unit is further configured to receive data related to the function from at least one of the first external server (S325), the second external server (S333) and the storage unit of the display device (S335) according to the determined provider, and to execute the function based on the received data, whereby, when the provider determined by the control unit based on the recognized keyword is the first external server (S319, YES) or the second external server (S327, YES): the control unit is configured to execute the data related to the function only when the provider determined by the control unit based on the recognized keyword matches the provider determined by the determination module. <EOS>