Generally, computer maintenance is a cyclical process that ensures that the computer remains functioning properly and prevents any critical problems that may occur later on. Computer maintenance is divided into two parts: maintenance of hardware in computers, and maintenance of computer software (in English: software).
Computer maintenance is an important process, it helps in the early detection of any problems, and it works to detect the presence of viruses or unwanted software that may harm the device significantly, in addition, periodic maintenance may lead to improve the performance of the computer, and improve the The effectiveness of its software. 
Principles of Computer Maintenance
Hard drive maintenance
The organization of data on your hard disk may be disrupted over time, or it may be corrupted because of the operating system, which always stores files, executes commands, Therefore, it is necessary to periodically maintain the hard drive to correct these imbalances by: 
Scan the hard disk and correct errors, if any.
Defragmentation of the hard drive.
In some cases, the hard disk may be damaged, and therefore difficult to repair, when the symptoms of damage to the hard disk, it is preferable to make backup copies of the data on it before it is too late, including: 
The overall performance of the computer is low, or it is constantly frozen.
The data on it is damaged; that is, the data becomes unreadable or usable.
Detect bad sectors when surveying them.
Hear unusual computer sounds, especially the so-called English click (death of).
Operating system maintenance
It is preferable to occasionally remove unused software and temporary files stored on the device, as well as a periodic update of the operating system and software, especially anti-virus software (in English: AntiVirus); This is especially important from time to time, in order to avoid loss of files in the event of an accident. 
The accumulation of dust over time causes the computer to overheat, which can cause the device to freeze during work or sudden errors, and its performance may drop dramatically, especially after a period of use, all of which will compromise the effectiveness of the device over time. It is advisable to clean the device periodically by cleaning the case inside and out, as well as cleaning the mouse, keyboard, and monitor.  
Causes of some common computer problems
Also called the Blue Screen of Death, a screen that appears in Windows shows a major system malfunction, and the user can only complete the work on the device by restarting it.  Common causes of blue screening include: 
Conflicts between computers installed.
Increase the temperature of the device, especially the CPU and the video card inside.
Corruption of one of the RAM cards in the device or corruption of several cards.
Errors in the hard drive.
Error programming system settings.
The computer may be exposed to sudden freezing during work, so that the user can not complete work on it, and the reasons for the freezing of the computer include: 
The mouse is damaged, so that the problem is in the mouse itself and not in the system, so replacing or reconnecting the mouse may solve the problem.
Increased CPU temperature due to ventilation error.
Device drivers error.
A bug in the software installed on the device.
The presence of viruses in the system of the device.
There are several reasons that can lead to a slow computer, including: 
Run many programs at once.
The presence of software that may consume most of the computer power.
The presence of viruses in the system.
Hard disk defect.
Limited RAM space.
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