The function of memory card is equivalent to the negative film of traditional film camera, and it is the carrier of image data. CF card, SD card and xqd card are usually used in digital SLR camera. In these three kinds of memory cards, SD card and CF card are more mainstream. The performance of memory card depends on its reading and writing speed. At present, the read-write speed of the memory card on the market is very strong. The write speed of the new generation CF memory card < / P > < p > card has exceeded 400MB / S; the read-write speed of SD card generally reaches 100M / S; and the read-write speed of the new xqd memory card is also as high as 400MB / s. gather and watch! Huawei P40 Pro evaluation: excellent mobile phone photography elegant design, do you like it?