Types of Memory for Computers
Hard Drives, CD/DVD's, Flash Memory by Johnna Roussos
A Hard Drive uses a magnetic field to memorize the data, images, and information. The actuary head presses on the wheel. The Hard Drive saves the memory unlike the RAM which has to receive the memory each time. A Hard Drive is the cheapest cost for saving memory. It costs $0.03 per gb.
The bumps on the CD are spiral. If the spiral is unraveled it equals about 5 kilometers. It uses a dye which is reflective or non-reflective. A laser reads the bumps. It costs $0.07 per gb.
Flash memory is at a non-volatile state. It is at a solid state. It is very fast and compact. It works with the binary system. It works great with portable devices such as laptops, cameras and MP3 players. It is very expensive to erase. The cost of the flash memory is still quite expensive at $0.90 a gb.