Removable Memory
Just what is removable memory? Removable Memory is just what is sounds, memory that can be removed from the computer without having to shut it down. There are many different kinds of removable memory, and each requires a different reader to read and write to the medium.
disk drives
DVD Drive
The Disk drive is a drive that runs on either IDE, or SATA and allows for removable disks to be read and used. These disk include, CDs (Require CD, DVD, or Blu Ray player), DVDs (Requires DVD Player, or Blu Ray Player), and Blu Ray disks (Requires Blu Ray Player). Blu Ray Players can play all media disks, DVD players can play DVDs, and CDs, and CD Players can play CDs. Blu Ray Players use only SATA, while DVD players can use either IDE, or SATA depending on the speed of the DVD unit, CD players can only use IDE.
floppy disk drives
Floppy Disk Drives or Floppy Disks are a far older version of removable media, originally developed in the 1960s, and only got up to 4.2 Megabytes of space, they were the pinnacle of technology when they were released. They have been replaced by Optical Disk drives, and the various flash memory devices that hold much more data, and are much faster. These are almost completely phased out, and do not exist in most modern PC's.
usb (flash) drives, and SD cards
Otherwise known as Flash Memory, these devices are "Hot Swappable" meaning you can remove them without having to shut down your system. These devices are used in many things such as cameras, MP3 Playes, Ipods, phones (Some phones can be used as Flash Drives), and in USB Thumb Drives. They are very portable and can hold a large amount of data. Some Flash Drives can hold 100 gigabytes of date. Most however go from 2-32 gigabytes of data. There are two common versions of USB today. 2.0 and 3.0. 2.0 is the most common, and has a max speed of 60 megabytes a second, while USB 3.0 goes up to 6 gigabytes a second USB 3.0 is backwards compatible with USB 2.0 and vice versa.
Flash Card Speed Class
Memory cards have a speed class rating, which determines what the card is good for (Usually used when deciding what recording's it can do)
Flash Drive speeds based on Samsung specs.