A system comprising: a removable IC card; and a mouse device including: a device casing provided with an operation portion (12, 13, 14) adapted to operate a host equipment, and connected to the host equipment, wherein the device casing comprises: a loading portion adapted to receive the IC card within the device casing; a connecting portion provided at one end of the loading portion for electrically connecting the IC card to the mouse device; and an insertion hole through which the IC card is inserted into the loading portion, characterised in that: one surface of the IC card is provided with a fingerprint detecting portion; the mouse device further includes an opening portion within the device casing into the loading portion which exposes the fingerprint detecting portion of the IC card to the outside of the device casing; and wherein the fingerprint detecting portion is exposed to the outside of the device casing through the opening portion by loading the IC card with respect to the loading portion. a removable IC card; and a mouse device including: a device casing provided with an operation portion (12, 13, 14) adapted to operate a host equipment, and connected to the host equipment, wherein the device casing comprises: a loading portion adapted to receive the IC card within the device casing; a connecting portion provided at one end of the loading portion for electrically connecting the IC card to the mouse device; and an insertion hole through which the IC card is inserted into the loading portion, characterised in that: one surface of the IC card is provided with a fingerprint detecting portion; the mouse device further includes an opening portion within the device casing into the loading portion which exposes the fingerprint detecting portion of the IC card to the outside of the device casing; and wherein the fingerprint detecting portion is exposed to the outside of the device casing through the opening portion by loading the IC card with respect to the loading portion. a device casing provided with an operation portion (12, 13, 14) adapted to operate a host equipment, and connected to the host equipment, wherein the device casing comprises: a loading portion adapted to receive the IC card within the device casing; a connecting portion provided at one end of the loading portion for electrically connecting the IC card to the mouse device; and an insertion hole through which the IC card is inserted into the loading portion, characterised in that: one surface of the IC card is provided with a fingerprint detecting portion; the mouse device further includes an opening portion within the device casing into the loading portion which exposes the fingerprint detecting portion of the IC card to the outside of the device casing; and wherein the fingerprint detecting portion is exposed to the outside of the device casing through the opening portion by loading the IC card with respect to the loading portion. a loading portion adapted to receive the IC card within the device casing; a connecting portion provided at one end of the loading portion for electrically connecting the IC card to the mouse device; and an insertion hole through which the IC card is inserted into the loading portion, characterised in that: one surface of the IC card is provided with a fingerprint detecting portion; the mouse device further includes an opening portion within the device casing into the loading portion which exposes the fingerprint detecting portion of the IC card to the outside of the device casing; and wherein the fingerprint detecting portion is exposed to the outside of the device casing through the opening portion by loading the IC card with respect to the loading portion. one surface of the IC card is provided with a fingerprint detecting portion; the mouse device further includes an opening portion within the device casing into the loading portion which exposes the fingerprint detecting portion of the IC card to the outside of the device casing; and wherein the fingerprint detecting portion is exposed to the outside of the device casing through the opening portion by loading the IC card with respect to the loading portion.