In Japanese Calligraphy, the primary modus peregrinations of Shingyōsō from ancient India to present day Japan, we find the styles of writing divided up generally into three categories of formalities. The first (shinsho 真書, which is also referred to as Kaisho (correct, square writing; 楷書)) being quite crisp and font-like, often times with sharp serif while other times without any such flourishes. This would be used for more clerical situations such as temple administrative documentation.
The second (Gyōsho), semi-formal style, would be the equivalent to general handwriting found in English, commonly used for daily communication, note-taking, and illustrates a bit of character from the author.
The third (Sōsho), least formal, would equate to cursive writing in English. This grade of calligraphy is the most expressive, generally thought of as most beautiful and art-like, and usually requires tremendous practice to be able to reproduce, while also requiring special training to be able to read correctly, even then one is usually expected to simply appreciate the qualities rather than try to understand them (Tathāgata; तथागत).
Each of the styles of writing is expected to be used in the appropriate context: Shinsho for official and government documents and archival purposes; Gyōsho is for common communication, and often used in advertising to allow leeway for some eye-catching flourishes and colors; and Sōsho which is used almost exclusively in the artistic expression of Shodō. From this, the term Shingyōsō can come to be thought of as a system of observing appropriateness.