A reader for a smart card, comprising - acquisition means for acquiring biometric data from a user, - derivation means (128, 130) for deriving an identifier from a combination of the biometric data and a further identifier, - a keypad for inputting the further identifier, - release means (120, 128, 136) for releasing a smart card function with the identifier, and - communication means (120, 144) for enabling communication between a computer and the smart card for use of the smart card function by the computer, wherein the derivation means are configured to carry out a one-way function in order to derive the identifier from the combination of the biometric data and the further identifier, wherein the biometric data and the further identifier are linked to one another by a logic XOR operation and, as a result of this linking, the one-way function is used in order to thus obtain the identifier, wherein the acquisition means comprise at least a first sensor (122.1) for acquiring a first biometric feature and a second sensor (122.2) for acquiring a second biometric feature, wherein the first sensor is associated with a first smart card type and the second sensor is associated with a second smart card type, and comprising query means for querying the smart card type from the smart card, wherein the acquisition means are configured such that the first sensor or the second sensor is selected for the acquisition of the biometric data depending on the smart card type of the smart card, wherein a first one-way function (130.1) is associated with the first sensor, and wherein a second one-way function (130.2) is associated with the second sensor, wherein the derivation means are configured such that the first one-way function is used to derive the identifier if the biometric data have been acquired by the first sensor, and such that the second one-way function is used to derive the identifier if the biometric data have been acquired by the second sensor. - acquisition means for acquiring biometric data from a user, - derivation means (128, 130) for deriving an identifier from a combination of the biometric data and a further identifier, - a keypad for inputting the further identifier, - release means (120, 128, 136) for releasing a smart card function with the identifier, and - communication means (120, 144) for enabling communication between a computer and the smart card for use of the smart card function by the computer, wherein the derivation means are configured to carry out a one-way function in order to derive the identifier from the combination of the biometric data and the further identifier, wherein the biometric data and the further identifier are linked to one another by a logic XOR operation and, as a result of this linking, the one-way function is used in order to thus obtain the identifier, wherein the acquisition means comprise at least a first sensor (122.1) for acquiring a first biometric feature and a second sensor (122.2) for acquiring a second biometric feature, wherein the first sensor is associated with a first smart card type and the second sensor is associated with a second smart card type, and comprising query means for querying the smart card type from the smart card, wherein the acquisition means are configured such that the first sensor or the second sensor is selected for the acquisition of the biometric data depending on the smart card type of the smart card, wherein a first one-way function (130.1) is associated with the first sensor, and wherein a second one-way function (130.2) is associated with the second sensor, wherein the derivation means are configured such that the first one-way function is used to derive the identifier if the biometric data have been acquired by the first sensor, and such that the second one-way function is used to derive the identifier if the biometric data have been acquired by the second sensor.