Data Storage
This article lists the various computer information systems/storage types and how they work. This article includes definitions of various types of storage, from hard drives and flash memory, such as USB drives and solid state drives (memory cards), to optical discs and smart cards. We currently use smart cards more than this article suggests.
Storage System
Random vs. Sequential
Random vs sequential access
When thinking of storage systems, one could presume that all of your data in one folder is located next to each other within the hard drive. This is false when talking about random access. With random access your information can be pulled from any location on the disk. Meaning, your one folder could have its data scattered about the physical hard drive. The benefit of this type of storage is that you could access data in any order. Think of it as your CD player, your favorite song ends and you want to hear it again just hit back and you instantly hear it again. It’s fast and nearly instantaneous, unlike sequential. You could think of sequential access like a cassette within a cassette player. When a song finishes and you want to listen to it again, you must rewind the cassette, or if you want to skip a song you must fast forward the tape. This is used with magnetic tape drives which, are used for backup purposes. Even though in random access media devices may seem like data could be misplaced or somehow lost in the sea of data. When created, every file is given a unique name by the computer system, other wise called addressable media, in order to keep tabs on all the data.
CDROM-Random Access
Tape-Sequential Access
Random access and sequential access of data are two separate ways a computer can access data. Random access is the ability to access data in any given location within the hard drive, quickly and efficiently. Most computers use random access today, because it saves the user time, as well as avoids confusion. Sequential access requires data being accessed in a sequence. Examples of sequential access would be: data on a disk file, or magnetic tape data storage. This can be useful to some users, if they are purposely attempting to process a sequence of data elements in order. However, this can also be time consuming for users who are trying to find a certain file on a disk or tape, which requires skimming through all of the data in a sequence. An example of a comparison between random access and sequential access would be the A-Z method. Sequential access would inquire the user to go through letters A-Z to achieve the goal of meeting point" Z"; whereas with random access, the user is able to jump directly to point "Z".