Operating System Fundamentals
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best answers from c, Lesson 2 C# Windows Forms
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- Hard disks are common IO resources
- How is Data Structured on a Magnetic Disk
| What are Partitions Partitions are logical divisions of a hard disk. That is, you divide your hard disk into sections that will be used for different purposes. You could create multiple partitions if you want to install multiple operating systems. (When you boot your computer and select the operating system to use, it will use the appropriate partition, and ignore the others) You could also partition a hard disk so that you can store files using two different file systems, or so that you can provide additional security for your files (for example, if you store your personal files on a different partition than your operating system and software, then your files will be less likely to get infected by a virus. Partitioning a hard disk has other file system benefits, such as reducing the size of file clusters (which results in less wasted space as more files are stored on the disk. Hard disks are common IO resources Operating System Fundamentals 71 A hard disk can only have four primary partitions, each of which could be used fora different file system and/or operating system. A partition that contains an operating system is called an active partition. However, once an operating system is installed, you can select a partition and further divide it into logical drives (each of which would be assigned a drive letter. Although the data on logical drives is not physically isolated (as it is in partitions, each logical drive appears as if it were a separate disk for file management purposes. This could be useful for organizing file storage, or for allocating logical drive space for the exclusive use of different computer users. How is Data Structured on a Magnetic Disk Data on magnetic disks is physically organized using tracks, sectors and clusters. On hard disks, data is also organized using platters (a floppy disk has only one platter, while a hard disk can have several physical platters, which are each organized into tracks, sectors and clusters. A track is a concentric circle on a disk or platter. A sector is a division in a concentric circle. A cluster is the smallest unit of storage space available on a disk. The larger a hard disk is, the bigger the clusters become. On a floppy disk, the cluster size is the same as the size of a sector (512 bytes. Figure 5.5 (below) shows the organization of tracks and sectors on a floppy disk. Download 2.34 Mb. Share with your friends:
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