Sometimes, though not that often, one comes across files that require conversion from one format to another to be able to exploit their full potential, or to make them functional on different hardware types, a good example being converting a DVD movie into Windows Media (.avi) or MPEG (.mpg) format. One can also convert image files, such as conversions from true colour to grayscale. Other file conversions can be applied to office file formats (word-processors) and audio file formats.

Some files are easily converted whilst others are notoriously difficult, and good knowledge of the file converting software would be required. A typical example of a difficult file conversion is a Portable Document File (