A good chunk of the introduction to this article made me cringe actually  There are way too many parentheses and comma and at times it seems like there is a stretch for more wikilinks  I tried rewriting a sentence and I could barley understand what its purpose was  Below is a new version of the introduction that I think is more clear and still contains the relevant information for someone looking for more information  Ill wait for comments before putting it on the main page   A container or wrapper format is a metafile format whose specification describes how data  and metadata is stored not coded  A program able to identify and open a container file might not be able to decode the contained data  This can be caused by  the program lacks the required decoding algorithm or the metadata does not provide enough information  By definition a container format could wrap any kind of data  Though there are a few examples of such file formats eg Microsoft Windowss DLL files most container formats are specialized for the specific requirements of the data   For example a popular family of containers is found among multimedia file formats  Since audio and video streams can be coded and decoded with many different algorithms a container format can be used to provide a single file to the user