This program is provided by Scott, who writes:
This might be over the time limit, but I cannot reduce this any more and still be able to paint the full historical picture.
Some of the songs are on the longer side, so the direction is: listen to enough to get a "feeling".
A couple of the bands, like Black Sabbath, Metallica, and Slayer have multiple songs, since they are critical to the genre.
I put "Explore More" on the right side if people want to spend more time than is required.
The textual explanations (mostly from Wikipedia) are also important to the narrative.
I purposely didn't use "music videos", since they didn't exist when most of these songs were created, and they generally distract from the music unless it was a co-conceived. In some cases, though, like glam metal, the visual aesthetic is probably as important (if not more than) the musical expression.
You will find the playlist on a separate web page provided by Scott:
Metal History, Part I