The 10 Best Micro SD Cards
Enter the World of SD
SD is the original version and it supports up to 2GB of capacity.
Secure Digital High Capacity, or SDHC, is the improved version that holds up to 32GB.
Strap yourselves in ladies and gentlemen, and keep your hands and feet inside at all times. We are about to embark on a wild ride down memory format lane, and it gets quite dense.
SD, also known as Secure Digital, was jointly created by tech giants Panasonic, Toshiba, and SanDisk as a way to improve upon the existing portable memory card formats. It quickly beat out rivals CompactFlash and MMC to become the current industry standard for memory card formats. Since its introduction in 1999, SD cards have evolved to cover a large variety of formats. They are classified in many ways: specifications, size, capacity, and speed class.
SD cards fall into three specifications: SD, SDHC, or SDXC. SD is the original version and it supports up to 2GB of capacity. Secure Digital High Capacity, or SDHC, is the improved version that holds up to 32GB. Secure Digital eXtended Capacity, or SDXC, boasts the highest capacity of up to 2TB. The latest version of SDXC cards are designed to support 8K video footage as well. While all SD cards are physically identical, SD host devices cannot support later version cards. Nonetheless, earlier versions of SD and SDHC cards can be used in SDXC slots, a concept known as backwards compatibility.
SD cards range in size: SD, miniSD, or microSD. All sizes can be specified as SD, SDHC, and SDXC and both miniSD and microSD cards can, with the aid of an adapter, fit into standard SD slots.
SD cards are also labelled by their capacity. A 4GB card will hold twice as much as a 2GB card. The current capacity standard is 64GB, however, they range from extremely limited (32MB) to extremely large (200GB). Contrary to belief, the physical size of the card does not correlate with the capacity. In fact, most microSD cards hold the largest capacity.
The final distinction is speed class; a rating system used to define how fast data is read or written on SD cards. It can range from Class 2, writing data at 2MB/s, all the way to Video Class 90, writing data at 90MB/s. The latter is optimal for 8K video footage.
Down the Rabbit Hole
SD cards are non-volatile, meaning data is not destroyed when the power source is cut off. This feature makes them a great option for portable electronic devices: camcorders, action cameras, smartphones, and E-books. MicroSD cards have risen to prominence in the world of smartphones due to their small size. Action cameras, such as the GoPro and the drone, are also using microSD cards as the standard memory card format.
Some microSD card manufacturers will entice the buyer with additional physical features for the card.
Some microSD card manufacturers will entice the buyer with additional physical features for the card. Important attributes detail if the card is waterproof, shockproof, or magnetic proof. These features might not tempt every consumer, however, they are worthy for anyone operating a durable camera like a GoPro.
Newer models of microSD cards can run applications as well. The aggravated Android user experiencing limited internal storage on his or her phone can now opt to run some applications off of the microSD card, creating more internal storage. This is not ideal, as the application will run slower in most cases from the external memory card.
Since most laptop computers are now designed to have built-in SD card readers, it's important to secure an adapter for your microSD card. Do not assume it is included with your purchase.
A Brief History of SD Cards
Secure Digital was created in 1999 by the SD Association: a joint account by Panasonic, Toshiba, and SanDisk. It was prompted into creation to correct the technical issues that faced CompactFlash (CF) and MMC; the existing memory card formats on the market. The SD Association vowed to invent a better portable memory card format. By doing so, they created the industry standard.
In 2005, the smartphone world demanded larger memory with a smaller memory card.
In 2000, the SD Association introduced the first version of the SD card. The model offered a mere 32MB of capacity. By today's standards, that limited storage is laughable. Since then, the Sisyphean task of keeping up with today's high resolution televisions and advanced smartphones has led to SDHC and SDXC formats to support the large amount of data.
In 2005, the smartphone world demanded larger memory with a smaller memory card. SD replied with the microSD card, compact enough to fit inside smartphones while holding up to 128MB of capacity. Obviously the capacity of microSD cards has exponentially increased in the past decade. In 2015, a microSD card was released that holds 200GB of data. The numbers will only rise: we don't know how high the glass ceiling will go.