Trouvé sur europe.sdcard.com ...
Citation
SD Memory Card
What is the difference between the "SD Memory Card" and the "MultiMediaCard (MMC)" and how are they positioned?
Since the SD Memory Card and MMC have the same surface size, upward compatibility is maintained by enabling the MMC to be inserted in a SD card slot. We are also maintaining the superiority of the SD Memory Card over the MMC in each of the aspects of "advanced copyright protection", "future capacity expansion", "fast data transfer rate and "write protection switch".
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Is copyright protection applied to all kinds of data saved on the SD Memory Card?
A. No, copyright protection is not applied to all kinds of data. The SD Memory Card decides whether copyright protection should be applied according to the data's application specifications. Currently, copyright protection is applicable to "SD audio" only, among standardized products.
En gros ça dit que les cartes ont la même taille, que les MMC peuvent être insérées dans un slot prévu pour SD-card.
ça dit aussi que les SD un taux de transfert (plus?) rapide, un "loquet" de protection (comme sur une disquette), et un système de protection de copyright (qui à pourtant été abandonné depuis ... me semble t-il

??? les "vieux" appareils "SDMI compliants" encore vendus activent la protection .. à éviter donc)
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