Hiberfil.sys: When you put your computer into hibernation, Windows XP will write all the memory contents into Hiberfil.sys file before shutting down the system. Then, when you turn on the computer again, the operating system uses Hiberfil.sys to put all the information back into the memory, and the computer returns to the state before it was turned off. However, Windows XP left the Hiberfil.sys file on the hard disk, although it was no longer needed.

Hiberfil.sys file may be very large, which is a special system file that Disk Defragmenter can't organize. Therefore, the existence of the file Hiberfil.sys will prevent the disk defragmenter from completely defragmenting.

Follow these steps to delete the Hiberfil.sys file from the hard disk:

The following steps will delete the Hiberfil.sys file from the hard disk:

Open the control panel and double-click power management.

Select the Hibernation tab in the Power Management Properties dialog box.

Uncheck the Enable Hibernation check box and click the OK button.

Once the Enable Hibernation check box is cleared, Windows XP will automatically delete the Hiberfil.sys file from your hard disk. After defragmenting the disk, you can re-enable hibernation.

Pagefile.sys: pagefile.sys is a system file (Win386.swp under Windows 98), and its size often changes by itself. It may be only a few tens of megabytes when it is small, and it may be hundreds of megabytes when it is big. Therefore, there is no doubt that pagefile.sys is a virtual memory under Windows, and its function is basically similar to that of physical memory, except that it is the "backup force" of physical memory. As we all know, although hard disk is not as fast as memory, memory can't be compared with hard disk in capacity. When running a program requires a lot of data and occupies a lot of memory, the memory will be "stuffed", and the temporarily unused data will be placed on the hard disk, and the space occupied by these data is virtual memory. In the memory, the page file is the reserved file of the hard disk. When the data in RAM has not been used recently, it can be used as extended RAM. You can read page files from adjacent data blocks on the hard disk, which is much faster than reading data from many different source locations again. Windows NT administrators or users can reset the default size value of page files provided by the system to meet other special needs. In other operating systems, page files are also called swap files or swap partitions. (It's a system page file, which is related to your hibernation. It is usually equal to your internal promotion size or virtual memory size. It can be deleted under other operating systems, but it will be automatically generated the next time you log in.

Actually don't worry, it won't affect the system.