These are the tutorial videos that you viewed in the campaign mode, assuming you played that. These are videos that show up in the help menu that show you how to do things. It is often helpful to have a visual aid to see what you need to do, and that is what these are for.
Reason for Creation
After coming to the conclusion that my game was too complicated for any player to understand on the first try, I realized that I needed to add some sort of help/tutorial information to the game other than just text tips which in my map making experience almost no one reads. One idea I had was to use in game tutorial videos, this is what is done in the SC2 campaign so I would assume players would be accustomed to this. So I went and found the trigger for creating an In-Game tutorial with a video, I imported my own video, and tested the map. The video did not work, so I went to mapster and the internet to find out how to get it to work. Surprisingly SC2 has been out 5 years and after searching it would seem no one has ever posted anything on how to make these videos works, assuming anyone outside of Blizzard knows. So after some reverse engineering I figured it out, and now I am posting this tutorial because, as I said, the solution to this problem does not seem to exist on the internet as of now.
Before we get started know that I just figured this out and there may be some steps that are unnecessary. I have neither the time nor desire to dig into this further to find out more, all I know right now is that I have a working method. Also as far as I know the software I recommended, that being Bandicam, ffmpeg, and VLC Media Player are spyware free.
How to Create an In-Game Tutorial Video
Recording the Video
Use whatever recording software you want, bandicam is free and works although it produces a watermark if you don't pay for it. Cam studio is free and I don think it has a watermark but I am not sure of the quality and im pretty sure it tries to install 3rd party junkware. At any rate record your video in 1280x720 resolution. I do not know if there are resolutions that are required, although there are two resolutions that almost all of blizzards videos are in and 1280x720 is the high-quality wide screen resolution that they use and it fits nicely in the help window. Record the video in the .avi format.
Now that you have your video, if you try to load it into Starcraft 2 the video will not be useable. There are a few things you must do first. First you must download a tool called ffmpeg. It is an open source piece of software used to do video conversion type stuff. You need to download a static build, 64 bit if you have a 64 bit OS and 32 bit if you have a 32 bit OS. Unzip the folder into any location you want. You then Want to go to your enviornment variables and add the path to the bin folder to your path variable. You can then open up a command prompt and use ffmpeg. I would strongly recommend using ffmpeg instead of something else, as it seems blizzard used an offshoot of this tool to do their video conversions so the codecs and what not are very similar. This youtube video is helpful for doing the setup.
Open up a command prompt. Then navigate to the location of your videos, in my case I went to C:\Users\<User Name>\Documents\Bandicam as this is where my recorded Bandicam videos are. Copy this path and change directory in your command prompt by typing: cd C:\Users\<User Name>\Documents\Bandicam. Now that you are in your videos directory, you need to run two commands. First you must remove the audio stream from your .avi video. When you record your video it will automatically generate an audio stream, and if your video has an audio stream it will not work In-Game. The command you type is: ffmpeg -i theTest.avi -map 0:0 -vcodec copy theTestOut.avi. This takes the video stream only and copys it into a new video file, that being "theTestOut.avi".
Now we need to run a second command, that being: ffmpeg -i theTestOut.avi -vcodec libtheora output.ogv. This will convert the .avi video you just made to .ogv format. This is important because the In-Game tutorial video trigger only recognizes .ogv videos, so it wont even be able to find the video if the video is not in the .ogv format. You can add an option to the command like so: ffmpeg -i theTestOut.avi -c:v libtheora -q:v 6 output.ogv. This option determines video quality which in turn affects video size. You can pick -1 to 10, I have 6 here. The higher the number the better the quality. I would also reccomend downloading VLC media player, becuase it can view .ogv files, wereas windows media player cannot. If you go under tools->codec information you can also get useful information about a video like its resolution, codec, and encoder. You can also see the streams in the video, so you can verify that the audio stream has been removed.
Import your video into the game like you would any other asset. In this case our video is "output.ogv". Go into the trigger editor, find the action "Create Tutorial" and add that. I put this action into a trigger that is run when a user types something but you can trigger this action however you want. Fill in the trigger with everything, including your imported .ogv video. Go into the game and after you trigger the action that creates the tutorial, click on the help "?" button and then click the tutorials button. Click watch movie and you should see your movie play.
This screenshot shows the in-game video I made, output.ogv. Its just me moving around the folder that contains my bandicam movie files. This was done without using the video quality option in the ffmpeg command, giving the default quality which as you can see is not very good.