A method for updating an embedded program of an electronic device including an electronic component, the method comprising: a common update data acquiring step acquiring common update data that is a common portion of updated version data of the embedded program, the common portion being able to be commonly used among a plurality of the electronic devices including different types and model numbers of the electronic components; a differential data acquiring step collectively acquiring differential data between the common update data and each updated version of the embedded program that is respectively applied to the plurality of electronic devices; a step acquiring update procedure data describing a sequence to update the embedded program of the electronic device using the common update data and the differential data; a model number acquiring step acquiring a type and a model number of the electronic component; and an update step (410, S407) updating, according to the sequence described in the update procedure data, the embedded program of the electronic device using the type and model number of the electronic component acquired in the model number acquiring step and using the common update data and the differential data, wherein: the update procedure data describes a correspondence relationship between the type and model number of the electronic component included in the electronic device and which one of the differential data is to be used; and the update step (410, S407) further specifying which one of the differential data is to be used using the correspondence relationship described in the update procedure data and the type and model number of the electronic component acquired in the model number acquiring step, and updating the embedded program of the electronic device using the specified differential data. a common update data acquiring step acquiring common update data that is a common portion of updated version data of the embedded program, the common portion being able to be commonly used among a plurality of the electronic devices including different types and model numbers of the electronic components; a differential data acquiring step collectively acquiring differential data between the common update data and each updated version of the embedded program that is respectively applied to the plurality of electronic devices; a step acquiring update procedure data describing a sequence to update the embedded program of the electronic device using the common update data and the differential data; a model number acquiring step acquiring a type and a model number of the electronic component; and an update step (410, S407) updating, according to the sequence described in the update procedure data, the embedded program of the electronic device using the type and model number of the electronic component acquired in the model number acquiring step and using the common update data and the differential data, wherein: the update procedure data describes a correspondence relationship between the type and model number of the electronic component included in the electronic device and which one of the differential data is to be used; and the update step (410, S407) further specifying which one of the differential data is to be used using the correspondence relationship described in the update procedure data and the type and model number of the electronic component acquired in the model number acquiring step, and updating the embedded program of the electronic device using the specified differential data. the update procedure data describes a correspondence relationship between the type and model number of the electronic component included in the electronic device and which one of the differential data is to be used; and the update step (410, S407) further specifying which one of the differential data is to be used using the correspondence relationship described in the update procedure data and the type and model number of the electronic component acquired in the model number acquiring step, and updating the embedded program of the electronic device using the specified differential data.