Difference between r4 and micro sd?

What is the difference of a micro sd card and a micro sdhc card ?

• what is the difference of a micro sd card and a micro sdhc card ?

• Answer:

  Both cards have the same physical dimensions. The only difference is that SDHC cards are capable of storing data greater than 2GB. The former is the original implementation of SD standard while latter is an extension that uses a somewhat different file formatting standard that enables it to store more data in each card. An SDHC-compliant device will be able to read both SD and SDHC cards. But a device that is not SDHC-compliant will NOT be able to read the SDHC card. Notice that I dropped the "micro" designation in above statements? That is because most, if not all, micro-SD or micro-SDHC cards -- or the slightly larger mini-SD or mini-SDHC cards -- come with a card adapter where you can slide the smaller chip into so that it can be inserted and read in regular-sized SD card slots.