Movies have the video data stream, audio data stream and subtitle data streams.
These have to be stored in a file.
Common containers are .MOV .MP2, .MP3 .MV4 or .MP4
Some formats like .MKV might be supported
Buying a wrong or defaulted drive will also result in losing all the data in a snap. Hence before buying external storage, you much check certain things in detail.try here: https://shops.ae/computers/accessories/removable-media/