There are plots of components in video2 /notebook 2. Like a bar chart. What does that plot represent?
Are you talking about the chart (at the bottom of this image)?
Here the x-axis represents all the different words, and the y-axis is how much they are a part of the 0th component/topic. This is illustrating that with NMF, a given topic consists of a relatively small number of words, and that most words have a value near zero (that is, most words are not part of the topic).