Commenting your code involves adding characters (normally slashes and stars) which mark certain areas of code as 'comments'.
Comments are used for reference information only and will not be run as part of your code. It is good programming practice to comment all functions, classes and methods in your code. This helps both the developer and others who might look at the code to understand its purpose.
Comments can be either single line or multi-lined:
// This is a single line comment.
/* This is
a comment
on multiple
lines
*/