SD Cards Explained ! - Everything You need to know about SD cards

Introduction

We all have used various types of SD cards and most of us don't even care about various types of SD cards available. Information is always useful and once you learn about various types of SD cards, I am sure, you would love to trade your card for even better one as per your requirements.

We all have different questions regarding SD cards like what SD ( or microSD) card is compatible with my host device and hwo do i choose the best card for my host device?

Types of SD Cards:

There are three main types of SD memory card family which are SD, SDHC and SDXC. 

SD 

SD stands for Secure Digital. Theire capacities ranges from 128MB to 2GB with default format FAT16. With the increasing requirement of storage, we started using SDHC and replaced SD cards with SDHC cards.

SDHC

SDHC stands for SD high capacity card which is based on the SDA 2.0 specifications. Their capacities range from 4GB to 32GB with default format FAT32. again, with increasing storage requirements, we started using SDXC and replaced SDHC with SDXC. 

SDXC

SD XC stands for SD extended capacity and they are actually based on SDA 3.0 specifications. SDXC capacities range from 64GB to 2TB with default format exFAT. 

Speed Class and UHS Speed Class Rating

Speed class ratings define a minimum guaranteed speed of SDHC/SDXC cards. Speed class rating is important for video recording and when the host device is actually streaming data or transferring data at a steady speed. The resolution and format of the video determine the amount of steady stream data. 

Class  Minimum Speed

Speed Class (SD Bus)

Class	Minimum Speed
2	2MB/s
4	4MB/s
6	6MB/s
8	8MB/s
10	10MB/s

UHS Speed Class (UHS Bus)

UHS Class	Minimum Speed
1	10MB/s
3	30MB/s

Compatibility

Now let's try to answer the main question, how can I buy the best card for my host device. The answer is simple, buy the latest that is supported for the device with higher class. In case of DSLR or other cameras, try to get a card with higher speeds than the recording speeds. Eg. A D3300 Shoots at 10MB/s and thus a UHS Class 1 card is better for working with D3300 as it gives a minimum speed of 10MB/s