What is difference between MKV and MP4?

In the process of converting .mkv to .mp4...?

• I have a few .mkv videos that I want converted to mp4. I know that .mkv has several audio files, in addition to subtitles. In converting .mkv to .mp4, will I lose those other audio files? For example, the file in question comes with japanese, english, french, and german audio, and the same for subtitles. I want the final .mp4 to have japanese audio and english subtitles. How can I specify what audio and subtitles stay in the final file?

• Answer:

  Finally others coming to their senses about freemake... 1. Open freemake video converter 2. Drag and drop the mkv file into it 3. Click on the audio that it shows for the file (a drop down menu will appear) pick the one you want 4. Click on subtitles (a drop down menu will appear) pick the one you want 5. Click on mp4 on the bottom so it converts to mp4 6. Set the path where you want it saved 7. Click on convert http://www.freemake.com/free_video_converter/