A quick survey of the unanswered beamer questions suggestions that about 20% of them are about problems with including multimedia files, such as videos or sound files. Many of them are about either using the wrong method for their file type (or the wrong file kind for their method) or use an unsuitable pdf viewer. Maybe this question can help to organise the information a bit.
There are different ways to include multimedia files in beamer, which one work and which ones do not highly depends on the pdf viewer you use and the operating system you are on.
This questions tries to summarize the main information about the different packages which can be used, one answer per package.
Packages covered in this Q&A:
Tools/Viewers covered in this Q&A:
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