The so-called "knot" in calligraphy refers to the structure of each word, which is also called "shelf structure". For example, the regular script structure of the word' three' is composed of three horizontal lines, of which the middle horizontal line is shorter than the upper horizontal line and the lower horizontal line is the longest. We say that the structure of this word is accurate, and vice versa. "Knot" is the minimum requirement in calligraphy! In all kinds of books, the "structure" of each word has different requirements, so we should pay attention to observation in our study.
Knot is one of the elements in appreciating the quality of a calligraphy!