sd means: It stands for Secure Digital. This is a memory card that can be used to store data on devices like digital cameras, PDAs and portable music players. It is one of smaller memory cards formats and measures 24x32x32mm in width by 2.1xm thick. The top corner of every SD card has a slanted edge to help orientation. The cards can store up to 8GB data, despite being extremely small. (in Computer Dictionary)

What else does sd mean?

  • The cards are known as “Secure Digital” because they have copyright protection built into them. Key revocation, which is a security feature that protects card data from being read by unauthorised devices, means the cards can be used only to access protected data. You can choose between secured or unsecure areas for both copyrighted as well as non-copyrighted data. Visit the SD Card Association for more information. (in Computer Dictionary)