The person that created this visualization used Microsoft Excel and Adobe Photoshop. They created their data using the IMDB website and the “all episodes” page within the website.
The visualization shows a chart where viewers can line up the episode numbers, which are placed on the y-axis and the season numbers, which are placed on the x-axis (above the graph), to see what the rating of that episode received. Each rating is based on a 1-10 scale using decimals to show an exact rating that the episode acquired. Viewers can also tell which episodes were better than others based on the color code included in the visualization. Each episode is colored based on the rating it received, the better the rating the greener the mark on the chart. In contrast, the lower ratings, the redder the mark on the chart.
I think that the chart used for this data visualization fits well with the information it is portraying. However, if I were to suggest another chart, I would recommend using a color-coded line chart to show the highs and lows that each season received. I would also suggest, if I were to keep the current chart style, changing the color ratings of each episode, the current colors become a bit blurred when they are rated in the middle. I would ideally suggest using a key with color codes to tell which episodes are great, average and terrible. These changes may provide viewers with an easier way of reading the chart. By using a color-coded key, viewers can easily see how many episodes are rated as average, great and terrible. They can then look more closely at the chart to see the actual rating that the episode received. Furthermore, by using a line graph, viewers can easily tell which season did the best based on the number of spikes within the line of each season.