MicroSD

microSD is a small removable memory card format used in mobile devices, cameras, and other portable electronics. It is the miniature version of the SD card, measuring 15 by 11 by 1 millimeters and using a standard 8-pin interface. The format was developed and standardized by the SD Association, with early contributions from SanDisk, Panasonic, and Toshiba, and is available in several capacity and performance classes through microSDHC, microSDXC, and microSDUC specifications.

Capacities and standards: The original microSD format supported up to 2 GB. microSDHC extended the range to 32 GB, microSDXC supports 32 GB to 2 TB, and microSDUC extends to higher capacities (theoretically up to 128 TB). Real-world cards commonly range from a few gigabytes to 1–2 TB. Not all devices support every format; older devices may only support microSD or microSDHC.

Speed and performance: Cards carry speed ratings that indicate minimum sustained write speeds or overall performance. These include Class 2, 4, 6, and 10; UHS Speed Class U1 and U3; Video Speed Class V6, V10, V30, V60, and V90; and Application Performance Class A1 and A2. Actual speeds depend on the card, controller, and host device. When selecting a card, higher ratings are typically needed for high-definition video, rapid photo bursts, or responsive app usage.

Usage and care: microSD cards are widely used in smartphones, action cameras, drones, and single-board computers. They can be used with adapters to fit standard SD slots. They are susceptible to counterfeit or mislabeled products, so purchase from reputable retailers, verify the card’s capacity, and back up important data. Formatting and compatibility may depend on the device’s operating system and file system requirements.