In recent years, memory and storage solutions have evolved to serve many types of products and media needs. There are different types of memory and storage, and each has its own purpose. In this article we review the different types of memory currently available. Most people use a combination of the storage devices explained below.

What is a memory card? memory and storage guide

A memory card or flash card is an electronic flash memory data storage device used for storing digital information. They are commonly used in many electronic devices, including digital cameras, mobile phones, laptop computers, MP3 players and video game consoles. They are small, re-recordable, and able to retain data without power.

•    SD stands for Secure Digital
•    SDHC is SD High Capacity: Typically come in capacities of 4GB to 32GB.
•    SDXC is Xtended Capacity: Typically come in capacities of 32GB+.


The Difference Between Speed Class and Speed Ratings for SD and SDHC Cards

The speed rating measures maximum transfer speed for reading and writing images to and from a memory card, expressed as megabytes per second. However, video doesn’t need as big a data pipe because the video format is a smaller “fixed stream” that uses only a portion of the data pipe.

Unlike card write speeds that measure maximum performance, class ratings measure the minimum sustained speed required for recording an even rate of video onto the card. The class rating number corresponds to the transfer rate measured in megabytes per second (MB/s). Class 2 cards are designed for a minimum sustained transfer rate of 2 MB/s, while Class 10 cards are designed for a minimum sustained transfer rate of 10 MB/s.

Rated Speed (i.e.-15MB/s, 30MB/s, ect.) is maximum speed for the card and also what you would expect to approximately see in typical usage of writing or reading files on the card. This measurement is pertinent to still photography, especially for taking pictures with high resolution and/or saving in RAW format where the files created are very large. The faster the card, the faster it can save the file and be ready to take another picture. You can really notice speed differences with high-megapixel DSLR cameras when using multi-shot burst mode.

Speed Class is a minimum speed based on a worst case scenario test. The Speed Class is important for video mode or camcorders, where the device is actually saving a steady stream of data. The resolution and format of the video determines the amount of steady stream data. This translates to a minimum speed you need to guarantee that the video captured on the cards is recorded at an even, sustained rate with no dropped frames (which would result in lost data or choppy playback).

UHS Speed Class is designed for SDHC and SDXC memory cards. UHS utilizes a new data bus that will not work in non-UHS host devices. If you use a UHS memory card in a non-UHS host, it will default to the standard data bus and use the “Speed Class” rating instead of the “UHS Speed Class” rating. UHS memory cards have a full higher potential of recording real time broadcasts, capturing large-size HD videos and extremely high quality professional HD.

SD Cards

Secure Digital (or SD) is a non-volatile memory card format for use in portable devices, such as mobile phones, digital cameras, GPS navigation devices, and tablet computers. SD memory card and SD host device are the terms for licensed products that meet SD standards.

SD technologies have been implemented in more than 400 brands across dozens of product categories and more than 8,000 models. For exceptional data speeds and unparalleled reliability, SanDisk SD cards help you capture high-resolution photos and HD videos with their industry-leading flash memory technology. SanDisk memory cards come in a range of capacities, offering ample space for storing photos, video and other data on cameras, camcorders and other SD-enabled devices.

micro sd card

microSD Cards

The SDA has extended the SD specification in various ways. It defined electrically identical cards in small sizes, including microSD. Smaller cards are usable in larger slots through the use of a passive adapter. The micro form factor is the smallest SD card format.

With the advent of smartphones and tablets, fast, reliable mobile data storage is more important than ever. Devices where small size is paramount tend to use microSD cards, and SanDisk microSD, microSDHC and microSDXC cards deliver the speed and capacity you need to get the most out of your mobile devices. And with their NAND flash memory architecture and proven reliability, SanDisk microSD cards are an ideal choice for OEM applications.

CompactFlash Cards

CompactFlash (CF) is a mass storage device format used in portable electronic devices. CompactFlash remains popular and is supported not only in many high end consumer devices, but in some professional applications as well.

The CompactFlash format was first specified and produced by SanDisk in 1994. Featuring SanDisk’s latest innovations in removable storage, SanDisk CompactFlash (CF) memory cards deliver the speed, capacity and reliability you need to capture stunning burst-mode photos and HD videos. With options available for amateur shutterbugs as well as professional photographers, these CF memory cards offer the speed, capacity and reliability you need.

SanDisk offers a broad selection of consumer CF memory cards ideal for use with point-and-shoot and DSLR cameras and HD camcorders. These memory cards deliver unmatched shot-to-shot performance, flawless Full HD video capture (up to 1080p) and enough capacity to store thousands of high-resolution images.

Memory Stick PRO Duo

A memory stick is a removable flash memory card format that offers blazing-fast transfer times and plenty of storage. Memory Sticks include a wide range of actual formats, including multiple form factors.

With a SanDisk Memory Stick PRO Duo™ memory card, you can expand the onboard memory of your Sony® camera, camcorder or game console. Featuring SanDisk’s innovative flash memory engineering, these memory cards bring greater reliability and faster performance to your Sony device. Taking photos and videos or saving your progress in your favorite game will be easier than ever.

For Sony camera and camcorder users, the Standard Memory Stick PRO Duo delivers enough capacity to capture your cherished memories. For PlayStation or PSP gamers, SanDisk’s exclusive Gaming Memory Stick PRO Duo memory cards transform your system into a full-features multimedia hub with more saved games, downloadable content, videos and other game data.

USB Flash Drives

The USB mass storage device class, otherwise known as USB MSC or UMS, is a protocol that allows a Universal Serial Bus (USB) device to become accessible to a host computing device, to enable file transfers between the two. To the host device, the USB device appears similar to an external hard drive, enabling drag-and-drop file transfers.

SanDisk USB Flash Drives offer a fast, convenient way to back up, share, carry and transfer your files. These Flash Drives provide enough space to store your photos, videos, music and other personal files. With their pocket-sized designs and expansive capacities, SanDisk USB drives let you take your files wherever you go.

From eye catching to purely professional, from low profile to flip top, these drives offer reliable flash memory storage. Virtually every SanDisk USB drive also provides SanDisk SecureAccess software, allowing you to protect your most personal data from prying eyes, no matter who borrows your drive or where you may happen to leave it.

Solid State Drives

A solid-state drive (SSD) is a data storage device using integrated circuit assemblies as memory to store data persistently. 

SanDisk Solid State Drives (SSDs) offer a high-speed, low power data storage solution for personal, OEM and enterprise computing needs. Providing improved performance for consumer and enterprise applications, SSDs have data speeds that are magnitudes better than traditional hard-disk drives (HDDs). SSDs also run cooler and use less power than HDDs, placing less strain on system resources.

For consumers, SanDisk SSDs offer the extra computational muscle needed to keep pace with next-generation games and applications. For enterprises, SanDisk SSDs deliver premium performance in both standalone and dual-drive cache acceleration setups. And since SanDisk manufactures SSDs to custom specifications and form factors, OEMs can rely on SanDisk to meet both design needs and performance requirements.

SanDisk Solid State Drives (SSDs) are high-speed, energy-efficient data storage solutions that provide improved performance for consumer and business applications alike. With their advanced architecture and tremendous data speeds, these SSDs outpace traditional hard-disk drives (HDDs) in every performance category. And since they have no moving parts, SSDs run cooler, create less noise, and use less power than HDDs—placing less strain on system resources.