Secure Digital (SD) cards aren't just for digital cameras anymore. While you used to need a "memory card" to hold all your photos, SD cards are now used not just in cameras but also music players, smartphones, tablets, laptops and more. While cameras might require an SD card for their primary storage area, other devices, such as smartphones, offer the ability to use an SD card to increase storage.
With so many choices available today, it is hard to determine what is best for you and what will work in your device. There are several different aspects to consider, such as speed class, physical size and capacity.
Not all SD cards offer the same speeds, and this may or may not be important to you. If you are a professional photographer taking photos in rapid succession, you will need the fastest SD card available to save the photos as quickly as possible. If you are just storing media files on your smartphone, speed isn't as important.
There are four different speed classes--10, 6, 4 and 2--with class 10 being the fastest and class 2 being the slowest. Class 10 is suitable for full HD video recording while class 2 is suitable for standard definition video recording.
SD cards come in many different sizes. The largest is the standard SD card, which is used in most consumer digital cameras. The smallest is the microSD card, which is used in most cell phones and smartphones that support SD cards. They are also used in other devices, such as tablets. miniSD cards are also available, but they are the least common size and aren't found in many devices. This is because microSD cards came along and were even smaller.
You often don't get to make the choice of what size SD card you want, as it is determined by what your device needs. You can't plug a microSD card into a standard SD card slot, though there are adapters that allow you to plug a smaller DS card into a larger SD card's form and fit it into the appropriate slot.
You will spend the most time thinking about what capacity you need in an SD card. They offer different amounts of storage, ranging from 1 MB to 2 GB in SD Standard Capacity cards, 2 GB to 32 GB in SD High Capacity cards and 32 GB to 2 TB in SD Extended Capacity. You will need to make sure your device supports SDHC or SDXC if you choose one of those cards.
You will need to buy the SD card that offers the right speed class, size and capacity for your needs. Confirm what your device supports before making a hasty purchase.