Here we are using the text Helloworld to demonstrate the naming patterns we are using in ROS:

• HelloWorld: This name starts with an uppercase letter, and each new word starts with an uppercase letter with no space or underscores.
• helloWorld: In this naming method, the first letter will be lowercase but new words will be in uppercase letters without spaces.
• hello_world: This only contains lowercase letters. Words are separated with underscores.
• HELLO_WORLD: All are uppercase letters. Words are separated by an underscore.

The following are the naming conventions followed by each component in ROS:

• Packages, Topics/Services, Files, Libraries: These ROS components are following the hello_world pattern.
• Classes/Types: These classes are following the HelloWorld kind of naming conventions, for example, class ExampleClass.
• Functions/Methods: Functions follow helloWorld naming conventions and function arguments are following the hello_world pattern, for example, void exampleMethod(int sample_arg);.
• Variables: Generally, variables follow the hello_world pattern.
• Constants: Constants follow the HELLO_WORLD pattern.
• Member variables: The member variable inside a class follows the hello_world pattern, with a trailing underscore added, for example, int sample_int_.
• Global variables: Global variables follow hello_world, with a leading g_, for example, int g_samplevar;.
•  Namespace: This follows the hello_world naming pattern.