What are the similarities between calligraphy and graffiti in form and connotation?

There are similarities between China's calligraphy and Chinese painting. Just as freehand brushwork is regarded as "the advanced stage of Chinese painting development", cursive script is the most expressive style of calligraphy, which can best express people's feelings and spirit, and is regarded as the highest pursuit by many calligraphers. In terms of painting, Ouyang Xiu once said that "ancient painting is painting without drawing form", which highlighted the pursuit of attaching importance to form rather than meaning.