When I invoke 'System Monitor' under the file systems tab it shows:
/dev/loop0 /KNOPPIX-DATA ext2 528.4 MB 125.8 MB 402.6 MB 76%
The used value of 402.6 MB (76%) has gradually gone up from minimal when Knoppix was first (Poor man) installed until now and I do not know why. I have not knowingly added anything apart from preferences I might make in various programs. My main usage is the Chrome browser. At the end of each session I clear browsing data and any downloads are moved to physical disk space and deleted from the downloads directory.
This figure is now too high and I want to reduce it by removing stuff that is not necessary. I thought I would use File manager for that so fired up PCManFM and looked at the /KNOPPIX-DATA directory and sub directories. There did not look much there at all. I looked at the properties of /KNOPPIX-DATA and the total size of files is 82.7 MB. I thought I would have a look inside the knoppix-data.img file by using another linux to extract the files from it. Again the files extracted came to a size of ~80+ MB.
So what is the other 319.9 MB used for and where is it so I can delete what is unnecessary!

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