Source code files

Source code files

Source code is any collection of computer instructions organized in simple text files in most cases.

All the instructions we’ll see in this curriculum: variables, functions, classes, etc.: represent the source code of an application

In java based projects the java source code is kept in files with extension: .java, example:,, etc.

  • Yet, you’ll often see files with other extensions like .properties, .txt, etc.
  • We’ll talk about them when needed

Every .java source code file should contain at least one class with the same name of the file.

e.g. /home/rodislav/MyProject/

public class Hello {
    public static void main(String[] args) {

Did you noticed the double hand ? "¯\\_(ツ)_/¯" this is a thing called: ESCAPING. Do you feel strong enough to google it ?

Hint: we speak about “special” characters.

Java file opened in simple text editor (with hightlight support)

image depicting a file which contains source code, opened in a text editor