Over the life of your computer it builds up files and folder in a temp folder. This folder is used by all kinds of software and for many reasons. Most if not all software does not delete these files so it's up to you to do that. Doing so will free up valuable disk space and help your system run cleaner.
The easiest way is to create a windows BATch file or delete them at the command line.
Copy and paste the code below into a file called DelTemp.bat somewhere on your computer.
Save the file and double click on it. It will delete most of the files and folders in your temp folder. I say MOST because there will be some files left that are currently being used. It is best to do this right at startup of your system.