SWF (Small Web Format/ShockWave Format) is a digital Adobe flash file format that stores vector-based animations, audios, and videos. Generally, it is used to stream media online, mostly browser-based games. Sadly, Adobe recently announced that they are ending Flash format support by the end of 2020 due to its shortcomings such as performance issues and lack of security.
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According to YouTube, MP4 video format with AAC audio codec and H.264 video codec is most recommended. However, this platform is also compatible with formats such as MOV, AVI, WebM, FLV, 3GPP, WMV, and more. Also, keep in mind that the maximum file size for YouTube is 128GB or 12 hours of playtime. So, you can use a video editor like Wondershare UniConverter to compress before uploading videos to YouTube.
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