Web server-side programming

Our entire discussion ignores the problem of server-side programming.

What happens if a request is made to the server?

Most of the time the request is very simple "send this file to me." The browser then interprets the file in the appropriate form: as an HTML page, a picture, a Java patch, a script program, and so on. More complex requests to the server often involve operations on a database (transaction processing). One of the most common is the issue of a database retrieval command, when the result is obtained, the server formats it as an HTML page and returns it as a result (of course, if the customer has higher intelligence through Java or some scripting language, the raw data can be sent and formatted on the client; it can be done faster, can also reduce the burden on the server). In addition, there are times when you need to register your name in the database (for example, when joining a group), or issue an order to the server, which involves modifying that database. This type of server request must be done through some code on the server side, which we call "server-side programming."

In the traditional sense, server-side programming is done with Perl and CGI scripts, but more complex systems have emerged. This includes a java-based Web server that allows us to use Java for all server-side programming, and the written program is called a "small Service Program" (Servlet).