What is human resource management

What is human resource management or HRM? Is this a good topic to choose for software development project?
How complex it will be to develop a prototype with minimum functionalities? Which database to choose? Please advice
What is human resource management?
Any organization or company is managed and developed by human beings or a person. Hence people are essential resource for the successful operation of the organization. Human Resource Management primarily involves making available the required number of people for a particular task, their recruitment according to skill sets for carrying out the tasks, appointment, managing their work hours and leave, remuneration and medical benefits etc.

Hence a system or software which helps the smooth documentation of the above mentioned database is Human resource management system (HRMS) for the organization. Within this software there should be different modules for staff database, payroll management, leave mapping, shift management, talent management etc.
As Saraniya explained earlier, you are chosing a very complex software project if you are taking HRMS as a whole!
I would suggest you to simplify the project scope to one particular section of HRMS, like Recruitment management or payroll system
Regarding selection of software, JAVA and PHP are the good alternatives,
Databases can be:
Oracle
MySQL
MariaDB