Excellent question! In practice, the Database is a tool for storing, organizing and consulting information. Its use is relatively well varied. The owner of a website or blog, for example, can provide an exclusive area for their readers. To make such access available, it previously collects some information, such as: Name, Additional Data, Address and E-mail, for example.
This information, after being sent by the reader, is stored in a Database. The vision that the website or blog owner has when he consults his database is the following: And then he will be able to manage this information in the way he thinks best for his business. There are several database managers, the best known are: MySQL, MS SQL Server and PostgreSQL. Furthermore, WordPress uses a Database to store all the necessary information.