Read more about Measurement Units of the amount of information
Numbers in binary system
Data and storage are necessary for the operation of computers and digital technology. Data is any information, from commands to files created by users, such as text or video. Data can be stored in different formats, but most often they are saved as a binary code. Some data are stored temporarily and used only during the execution of certain operations, and then removed. They are recorded on temporary storage devices, for example, in RAM, known as the storage device with arbitrary access (in English, RAM - Random Access Memory) or RAM is an operational storage device. Some information is stored longer. Devices providing longer storage are hard drives, solid-state drives, and various external drives.
Read more about data
Data is information that is stored in symbol form and can be read by a computer or person. Most of the data intended for computer access are stored in files. Some of these files are executable, that is, they contain programs. Files with programs usually do not consider data.
Overall array of independent RAID discs.
In order to avoid data loss during breakdowns, the principle of redundancy is used, that is, stored copies of data in different places. If this data is no longer read in one place, then they can be considered in the other. In this principle, the work of the redundant array of independent RAID disks is based (from the English Reduntant Array Of Independent Discs). It is stored on two or more disks combined into one logical block. In some cases, the RAID array itself is copied for greater reliability. Copies are sometimes stored separately from the main massif, sometimes in another city or even in another country, in case of destroying the array during cataclysms, disasters, or wars.
Data storage formats
Data storage hierarchy
The data is processed in the central processor, and the closer to the processor the device that stores them, the faster they can be processed. The data processing speed also depends on the type of device on which they are stored. The space inside the computer next to the microprocessor, where you can install such devices, limited, and usually the fastest, but small devices are closest to the microprocessor, and those that are more slower - further from it. For example, the register inside the processor is very small, but allows you to read data at a speed of one processor cycle, that is, within a few billion fractions of a second. These speeds are improved every year.
The primary memory includes memory inside the processor - cache and registers. This is the fastest memory, that is, the access time to it is the lowest. RAM is also considered primary memory. It is much slower than registers, but its capacity is much larger. The processor has direct access to it. In RAM, the current data is recorded that are constantly used to work performed programs.
Secondary memory devices, such as hard magnetic disk drive (HDD) or Winchester, are inside a computer. They store data that are not so often used. They are stored longer, and not deleted automatically. Basically, users or programs themselves are deleted. Access to this data is slower than to data in primary memory.
The outer memory is sometimes included in secondary memory, and sometimes they are attributed to a separate memory category. External memory is replaceable media, such as optical (CD, DVD and Blu-Ray), Flash memory, magnetic ribbons and paper media, such as cardiac cards and punched. The operator must manually insert such media into readers. These media are relatively cheap compared to other types of memory and they are often used to store backups and to exchange information from hand to hand between users.
Tertiary memory includes large-scale storage devices. Access to data on such devices is very slow. Usually they are used to archive information in special libraries. Upon request of users, the mechanical "hand" finds and places the carrier with the requested data into the reader. Media in such a library can be different, such as optical or magnetic.
Views of carriers
Information with optical carriers is read in an optical drive using a laser. While writing this article (spring 2013) the most common optical carriers are optical discs CD, DVD, Blu-Ray and Ultra Density Optical (UDO). The drive may be one, or there may be several of them combined in one device, such as in optical libraries. Some optical discs allow you to re-record.
Semiconductor memory is one of the most frequently used types of memory. This is a parallel memory memory that allows simultaneous access to any data, independently in which sequence this data was recorded.
Almost all primary memory devices, as well as flash memory devices - semiconductor. Recently, the solid-state SSD storage devices are becoming more popular as an alternative to hard disks (from English Solid-State Drives). While writing this article, these drives were much more expensive than hard drives, but the recording speed and reading of information on them is significantly higher. With drops and blows, they are damaged much less than magnetic hard drives, and work almost safe. In addition to high prices, solid-state drives, compared with magnetic hard drives, with time begin to work worse, and the lost data on them is very difficult to restore compared to hard drives. Hybrid hard drives combine the solid-state drive and magnetic hard disk, thereby increasing the speed and service life, and reducing the price, compared with solid-state drives.
Storage on hard magnetic disks
The surfaces for recording on magnetic media are magnetized in a specific sequence. The magnetic head reads and records data on them. Examples of magnetic media are drives on rigid magnetic disks and floppy disks that have almost completely outdated. Audio and video can also be stored on magnetic media - cassettes. Plastic cards often store information on magnetic stripes. It can be debit and credit cards, card keys in hotels, driver's license, and so on. Recently, some cards are embedded in some cards. Such cards usually contain a microprocessor and can perform cryptographic calculations. They are called smart cards.
Punch card for weaving machine
Perfocart and USB Flash Drive
Before the appearance of magnetic and other carriers, the data was stored on paper. Typically, the machine teams were recorded in this form, and they could read both people and cars, such as computers or weaving machines. Basically, for these purposes, punch cards and punctants were used, where the information was stored as alternating holes, and the absence of holes. Perflate used to record text on the telegraph and in the printing house or the newspaper editorial board, as well as in cash registers. Gradually, since the end of the 50s and until the end of the 80s, magnetic media were replaced. Now paper media are used to count the votes in the elections and to automatically check the test work, the answers to which are recorded on a special card, and then read by a computer.
Article author: Kateryna Yuri
Do you find it difficult to translate units of measure from one language to another? Colleagues are ready to help you. Publish a question in tcterms And within a few minutes you will receive an answer.
Consider how to translate a certain number of bits in bytes, kilobytes, megabytes and gigabytes.
It is known that in:
1 Bail - 8 bits.
1 kilobaite - 1024 bytes.
1 megabate - 1024 kilobytes.
1 Gigabay - 1024 megabytes.
Based on the above, you can make calculations:
To find out how many bits in the pate, you need, the number of bits are divided by 8.
Further, the obtained number (bytes) is divided 1024, so we get the number of bytes in kilob.
To obtain the number of kilobytes in megabytes, the number of kilobytes are necessary to divide by 1024.
For gigabytes, the number of megabytes is divided by 1024.
To obtain a reverse result, such as gigabytes to translate into megabytes must multiply the number of gigabytes by 1024.
To automate recalculations, in MS Excel, you can create the following converter (green data entry field).