As long as there are two stable material conditions that can be conveniently detected to identify which stable state they belong to, and these two stable states can easily convert into each other, such materials or components can be used to store binary codes "0" and "1". Such materials and components are called storage media or recording media. Different storage media have different mechanisms for storing information. Information storage technology has developed very rapidly in recent years, with various new products and technologies emerging one after another. However, overall, they present a structure similar to a pyramid. The top of the pyramid is the CPU, and the closer to the CPU at the top of the pyramid, the faster its storage speed. But the cost of storage is more expensive, and its capacity is smaller. Conversely, the slower the storage speed, the cheaper the cost, and the larger the capacity.
From the perspective of hard disk data storage system architecture, it can be divided into internal memory and external memory. Internal memory (i.e., RAM) is directly connected to the computer's CPU and is located at the top layer of the pyramid. Its storage speed must match the CPU, and its material is usually composed of semiconductor memory chips. Due to the high cost, the capacity is also smaller. For large amounts of data, we usually need to use external memory. However, external memory can also be divided into several levels. The one connected to the internal memory is the online storage (or called online storage). For example, hard disk drives, disk arrays, etc. The next layer is the backup storage (or called nearline storage), which is composed of equipment with slower access speeds than hard disks, such as optical disc drives, optical disc libraries, magnetic tape libraries, etc. The bottom layer is offline storage (or called offline storage), composed of magnetic tape drives or magnetic tape libraries, optical discs, etc. warehouses. Its storage relative to the CPU is already very slow, just at the second level. However, due to the ability of the storage medium to be stored offline and replaceable, the capacity is virtually unlimited.
For general personal computer users, using storage media such as hard drives and optical discs for data storage is sufficient. However, for enterprise users and network systems, magnetic tape drives and disk libraries, optical disc libraries are indispensable devices for data storage and backup. According to different storage media, let us look at the currently popular host information storage technologies in the market. They can be divided into electrical storage technology, such as memory, flash memory, etc., magnetic storage technology, such as magnetic tapes, magnetic disks, etc., and optical storage technology, such as CDs, DVDs, etc.
Therefore, what kind of information is stored on what kind of medium is something we need to consider. As for how to recover the information from these different types of media, this is what we will focus on introducing to everyone! Reprinted by Anhui Aite Data Recovery Center. Our aim is to introduce data recovery technology to the general public. We hope that every friend can be free from the shadow of data loss!