SD存储卡（Secure Digital Memory Card）是特别为符合新出现的音频和视频消费电子设备的安全性、容量、性能和环境等要求而设计的一种存储卡。SD存储卡包含符合SDMI标准安全性的版权保护机制，速度更快而且存储容量更大。SD存储卡的安全系统使用双方认证和“新的密码算法”技术，防止卡的内容被非法使用。它还提供了一种无安全性的访问方法访问用户自己的内容。SD存储卡的物理外形、引脚分配和数据传输协议都向前兼容多媒体卡（MultiMediaCard），但也增加了一些内容。
The Secure Digital Card is a flash-based memory card that is specifically designed to meet the security, capacity, performance and environmental requirements inherent in newly emerging audio and video consumer electronic devices. The SD Card include
FileRecovery for MultiMediaCard recover lost data from MultiMediaCard used by digital cameras. If you have unintentionally deleted or formatted pictures, videos or sound files on your data medium or have pulled it out during a write operation, not t
This device is intended to provide a flexible means of providing embedded Audio/video systems (TVs, DVD players, STBs, Portable Media Copiers or Players, etc.) access to Media files stored on Flash Media Cards such as Memory Stick (MS), Secure Digit
因为MMC后来与JEDEC合并，很多前MMC的标准和规范较难找到，分享给有需要的人。
The MultiMediaCard is an universal low cost data storage and communication media. It is designed to cover a
wide area of applications as smart phones, cameras, organizers, PDAs, digital recorders, MP3 player
