Anyone who has played a musical scale has played a mode. As explained in the video even by playing the same group of notes on the keyboard (ie the white notes). The root or starting note and the intervals that follow (by skipping the black notes not all the white notes are equally spaced in pitch) determines the sound, style, feel and emotion of any music you make within that scale or mode.
From modes to fonts – typographic scales vs musical modes.
A typographic scale is a series of font sizes that are proportionally related to each other. This creates a harmonious visual hierarchy, similar to how musical intervals create a harmonious sound.
Just as musicians choose notes from a musical scale, typographers select font sizes from a typographic scale. The ratios between these sizes can be based on musical intervals like perfect fourths, major thirds, or even the golden ratio.
Musical intervals, like perfect fourths (4:3), major thirds (5:4) and minor thirds (6:5), can also be used to create typographic scales.