Speed class when working with applications to which the memory card corresponds.
When working with applications that use a memory card (for example, mobile games), information is written and read not in a continuous stream, as when recording video or copying data, but in separate small fragments, and from random areas in the drive’s memory (the so-called random write/read). So a high-class video recording (see above) does not always mean good flow Rate when working with demanding games and other resource-intensive programs. Therefore, the characteristics of memory cards began to separately indicate the speed class for applications.
The key indicator for assigning a particular class is the minimum number of IOPS (input/output operations per second) that the media can provide in random write and read mode. Nowadays, the following classes are relevant:
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A1 — at least 1500 IOPS for reading and 500 IOPS for writing;
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A2 — at least 4000 IOPS and 2000 IOPS, respectively.
The continuous recording speed (for example, when recording video) in both cases must be at least 10 MB/s (often it is higher - see “Speed class”, “Video recording class”).
In the future, we can expect the emergence of new, more productive classes for applications. We also note that this parameter significantly affects the price of the card.
The coefficient describing the maximum speed of the card in read mode. In this case, 150 KB/s is taken as a unit; thus, for example, the speed value of 533x corresponds to 150*533=79,950 KB/s, i.e. about 80 MB/s.
In general, this parameter is quite specific; in practice, it is easier to focus on the directly declared reading speed (see below). However, sometimes it is not specified - in such cases, the speed value will be most useful.
