Sometimes we may face the problem that our system work slow.one of the region for this is, temporary and prefetch files are created automatically. Which occupies more space in RAM.by deleting these files permanently, we can speed up the system. Temporary files are created to temporarily contain information while a new file is being made. It may be created by computer programs. While we run any program for the first time the prefetching file is created automatically, which helps to load the page fast. These prefetch files help to improve the performance of the system. But more the prefetching files are leads to decrease in the speed of the system because it decreases the available space in RAM.
At the same time in C drive, so many unnecessary files are created like Temporary internet files, Setup log files, delivery optimization files, recycle bin files and thumbnails are created. If you observed your system is running slow, clean up the c drive using disk cleanup app, which is already installed along with OS.