The letters shown exhibit the distinct thick and thin strokes that are characteristic of writing created by a calligraphic pen.
This variation in stroke width is achieved by the angle and pressure applied while using the pen, which produces elegant, flowing lines.
The thicker strokes typically occur when the pen is pressed down more firmly or held at a certain angle, while the thinner strokes appear with lighter pressure or different pen positioning.
These features are hallmarks of calligraphy, giving the text an artistic and refined appearance that differs significantly from uniform, mechanically produced lettering.