One of the departments that can most affect the proper functioning of a company is the personnel department or human resources department. This is because, although it is not a department that has a direct function with respect to the product or service provided by the company, it is a department directly responsible for all employee-related matters, These will ultimately determine the company's product or service and, consequently, the company's success.
The personnel department or human resources department is the department that is in charge of the Human capital management of a company. In other words, it's the department that manages everything to do with the people who are or aspire to be part of the workforce of the company in question.
As mentioned, the general function of a personnel department is to manage all matters relating to the people working in a company. However, this type of management can be more varied than might initially appear. Some of the most common and important functions it handles are as follows:

It should be borne in mind that not all companies have a human resources department. Various elements influence this decision, such as, mainly, the number of employees in the company. As is evident, having a department with these characteristics allows for much more efficient and decisive management of matters in this area and, furthermore, also speeds up any of the procedures related to the human capital that the company has. In this way, it constitutes an important and valuable tool which, at least in the case of larger companies, is necessary and essential for the smooth running of the company.