Can you give some more info:
1. What OS (Windows 8 Pro or RT)?
2. How many disks and how many partitions (drive letters) on those disks? May be only c:, may be more.
3. The size and the percentage free of all partitions. In Computer, do a right click>properties on the drive to determine.
Then do Microsofts disc cleanup, as documented in http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/app_disk_cleanup.mspx?mfr=true and repeat #3.
Low disk space can mean that your disk is full, but also it can mean that you need to adjust your virtual memory settings. That's why I'm asking this.
Kees
My computer system is windows8. When I try to download something or just run some programs, a warning would show up and said that I have low disk space. How can I clear my disk space? Also, I wonder a simple disk defragmentation could be enough. Many thanks.
(Do I need to use a disk cleaner like Colorful Disk Clean? This program looks cheap and useful, or u guys have any other suggestions?)

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic