According to the query Life Encyclopedia and Baidu Encyclopedia, the time unit is every hour. The English word for hour is hour, abbreviated as HR. When doing math or physics problems, most units are abbreviated as H, abbreviated as hour units, but in different forms, but with the same meaning, there is no difference. At the same time, hr also stands for human resources. Human resources (HR) refers to people. The broadest definition refers to human resource management, including six modules: human resource planning, recruitment, training, performance, salary and labor relations. Mostly used in the company's personnel department. It is also an important position in the company. Personnel recruitment, training, employee assessment, employee salary and employee transfer are all related to personnel.

Time is the expression of eternal movement, continuity and changing order of matter, including two concepts: time and time period. Time is a parameter used by human beings to describe the process of material movement or the occurrence of events. The determination of time depends on the law of material circulation that is not affected by the outside world. The time measurement system based on the earth's rotation is called universal time system. Time measurement of time, day, month, year and century belongs to the calendar category in astronomy. Time is one of the seven basic physical quantities in physics, and the symbol is T. In the International System of Units (SI), the basic unit of time is seconds, and the symbol is S.