Simply put, this is a very light weight application that helps you see what all secrets microsoft is hiding in index.dat files in various folders under a user's profile. As per microsoft index.dat files are their cache or index files that they create to speed up access to various web sites, applications etc. But one thing lot of people have to come realize over the time that even after you clean up your Temporary Internet Files, Cookies, History etc. files from your windows machine, these index.dat files still carry all the footprints of your internet and file activities. So analysis of these files is used as one of the forensic tools when you want to recreate a user's internet activities in the past.
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