Both SD and micro SD cards serve the same purpose, that of sorting data. You can get a micro SD with the capacity of 64 Gb for example, and you can get a regular SD card with the same capacity. You can even go as far as getting a micro SD to SD adaptor to allow your micro SD to fit into your camera, but what exactly are the differences?
You'll quickly realise that a micro SD is substantially cheaper than the same capacity SD memory card. The reason for this is due to the writing speed.
Most professional photographers and videographers would strongly suggest investing in a lower capacity card with a higher writing speed than a memory card that has a huge capacity and a slow writing speed. But this all depends on the gear you are using.
Most modern-day cameras shoot at exceptionally high resolutions, which in turn make the file sizes that much larger. So, every photograph you end up taking will take a longer time to write to the card if it has a slower writing speed.
Micro SD cards, although very handy, useful and cheaper than regular SD cards, usually have a far slower writing speed than the regular SD.
Take a look at the video below by the YouTube channel, Dave McKeegan, on Using A Micro SD In Your Camera Instead Of An SD?