" Thumbs.db is a file used by versions of Microsoft Windows that stores a cache for Windows Explorer's thumbnail view. Thumbs.db is saved in each directory that contains pictures or photos.

Windows stores thumbnails of graphics files in the Thumbs.db file, including the following formats: JPEG, BMP, GIF, TIF, PDF, and HTM). Each thumbnail created in a directory is represented in this database file as a small JPEG file, regardless of the file’s original format. Each folder with initiated thumbnail views (that is where they have displayed a Thumbnails or Filmstrip view in Windows Explorer) will have a thumbs.db file. ".

Cái này e đoán là dùng qua thumbn vì khi e kik chuột phải chọn refresh thumbnailb thì cái hình con ma dễ thương lại hiện ra.