The most taboo thing about rulers is the scratching and blurring of the engraved value, so rulers become the most protected articles in stationery. The use of rulers should be correct. For example, it is better not to use plastic rulers when delimiting materials, which will easily be scratched. Many people will make a mistake, that is, they will draw the line very fast, and then they will run along the ruler because of the slippery characteristics of the ruler, which will make the value, so the speed is moderate.

Rulers used in different situations have different requirements and standards. If the value is more accurate, it requires higher technology and must be produced by machine. In addition to the requirement of accurate value, the second key is the quality of the engraved value. Generally, a protective film will be applied after the engraved value. The third point is the selection of materials, which are now divided into plastic, metal and wooden rulers, Plastic rulers are mainly used for stationery by ordinary students, metal rulers are more used in industry, and wooden rulers are mainly used for teaching.