In this video, I want to show you how the different methods, the different visual techniques you can use to group, to give a sense of object grouping together, relate one to another. As I said before, some are stronger than others. Let me start once again with the grid of squares. So, number of squares arranged in a grid. When you look at this, you can't really perceive any specific pattern. As soon as I color them, some of them, you perceive the squares that are colored the same as belonging to the same group as we have seen before. But now let's see what happens when I use more methods at the same time, multiple methods at the same time. So, now I'm taking the first row and I'm creating space between the first row of objects and the rest. What do you see here? I guess what you see is that there is one group of objects on top and one group of objects at the bottom despite the fact that they didn't change the coloring. So what do you see here? You see that despite the fact that color, as we saw in the previous slide, is one of the methods that you can use to group things together when space or position is used, position is stronger. Now, if I add that contour and group together with a line, some of these objects, those objects on the left, what do you perceive? You perceive these objects as belonging to a group, despite the fact that some of them are more distant and some of them have different colors. So, what does this suggest to you? It should suggest that contour, enclosing objects in a contour, in an area is stronger than the rest. Very similar to this last case is the case of connection. If I connect some elements together, the grouping that I perceive more strongly is the group of objects that are connected through lines despite the fact that some of them have different colors and some of them are more distant than others. So, that's the ranking of the grouping methods that we have seen so far. So in summary, what do we have? We have that you can group things together through similarity but that's the weakest method. After similarity, you have proximity proximity stronger than similarity. And then you have enclosure and connection that are stronger than the rest. These are very useful properties to keep in mind when you think about how to design a visualization and also what kind of effect certain design choices may have on what is perceived by the viewer.