Memory Card Types
Nearly every ebook reader on the market today comes with a card reader slot for adding more memory for the ebook reader itself. Memory, just like in many digital devices, is used for storing data on your ebook reader, including ebooks, movies, pictures, and music.
SD Cards
SD cards, or secure digital cards, are removable flash memory disks. They are the most common type of memory used in portable devices, and are easy to move from one portable device to another. This means you can use the same cards that you use for your digital camera in your ebook reader. These cards are usually rather small, and can range from 128 MB to 32 gigs. Currently, there are four common types of SD cards: SDHS (high transfer speeds, up to 32 gig), SD (up to 4 GB/second), mini/microSD (high transfer speed, up to 4 GB/s), and mini/micro SDHS (up to 32 gigs). Mini and micro-SD cards can be used in a regular SD card slot with an adapter, which can be helpful in loading content from a laptop or desktop onto the card.
Advantages: Inexpensive, interchangeable with other devices, easy to use, large storage sizes
Disadvantages: Easy to lose, not as fast as Compact flash
Memory Sticks (MS)
Memory sticks are exclusively used in Sony readers. These special memory sticks were designed originally for Sony cameras and other products. While these cards are interchangeable with other Sony items, few non-Sony items can accept them. There are currently two main types of memory cards sold for Sony ebook readers - MS Pro (holds up to 4g) and Pro Duo (Up to 32 gigs, faster).
Advantage: Use interchangeably with almost all Sony Products, large storage size
Disadvantage: Expensive, hard to find, not compatible with other brands of digital devices, slower transfer speeds than SD and compact flash
Compact Flash (CF) Memory Cards
A Compact Flash Card is a type of memory card for PDAs, digital cameras, ebook readers, tablets, and most other portable electronic devices. These cards use flash memory to store data on small cards. These cards are considered one of the most rugged and interchangeable types of memory for portable devices. Compact Flash Cards can hold anywhere from 2 MB to 128 GB. Compact Flash cards are rarely used in eReaders because of their size.
Advantages: Fast reading time, large storage size, durability.
Disadvantages: Large Size