When you do something using a PC, you are always supported by files and folders (directories)

• File
  
  • Application programs (software) and data (e.g. documents created by word-processing software, images taken using digital cameras) are saved (stored) in the form of a “file” (unit). A file has its own name and is indicated as an icon (small picture) on Windows.
  • To store an application program file in a PC, purchase or download the software and install it [put the software into the PC and prepare the environment to run it] in the PC.
  • Data files are stored in the PC by creating one using an application program or creating a copy using existing data.


• Folder (also called a directory)
  
  • This is something like a box (case) to store files.
  • Folders can be stored in other folders (sometimes called as subfolders).
  • Folders are created by the user (who operates the PC) using the functions of the OS.
  
  Folders exist to organize the files you created by using various application programs. For example, if many kinds of dishes are scattered in one lunch box, it does not look tasty and is difficult to eat. It is more attractive and more efficient if you divide them into multiple boxes (divide into folders), divide them into some blocks in the box (divide into subfolders), and in each block (folder), put the similar types of dishes (files) together.
  
  
  
  
  Copyright Ikue Iwata 2005, All Rights Reserved
  
  If many types of files are scattered in one folder, work efficiency declines. Creating folders and organizing files by purpose or by file type increases the work efficiency.
  

Like folders and files, a drive is a “box” to store files and folders, however, it is different from folders and folders which are virtual boxes; a drive is a physical box (storage medium).
There are three types of drives as shown below.

• Fixed drive
    This is called a hard disk and is generally built into a PC.
  The data stored in this type of drive can be used only by a PC with a hard disk that is built in.


• Removable drives
    Floppy disks, CD-ROMs, and USB memory are removable drives, and their characteristics are that the user can take them away or connect them to another computer.
    By storing data in this type of drive, for example, the user can use the data created in a PC in the university or at home.

Recently, USB flash memory has come to be commonly used as a removable drive. The price varies from 2,000 yen to around 20,000 yen depending on the capacity, however, in general, one with a capacity of 128 MB (around 2,500 yen) will be sufficient.


Here is an example of its usage for reference.


• Network drive
     This is the drive of a processor called a server on a network and is virtually shown as a built-in drive.
  For this reason, the data stored in this type of drive can be loaded from other PCs that share the same network.
  The disadvantage of this type of drive is that when the network is unavailable or the server has a problem, the drive cannot be used.

In Windows, drive names such as “A:”, “B:”, or “C:” are given to the drive automatically.

(Reference)
The information processing training system in Kumamoto University has the following structure. The U: drive is provided by the “home directory server” and the profile information that is loaded at login, such as the desktop environment, is stored in the “profile server” as shown in the figure below. The servers and PCs in the training room exchange large amounts of data through the network, however, we can enjoy smooth communications as the network of the University is supported by a high-capacity backbone network with a capacity of 10Gbp.