If you feel like some places in your code require additional explanation, use comments. Comments are non-executable blocks or lines of text aimed to describe some pieces of the code.
You can use double-slash "//" to write line comments. Rules are simple - everything after "//" is considered a comment to the end of line. You can use line comments to leave short notes for other developers or to comment out some code to remove it from the execution chain.
If you don't want to comment all the line contents, or if you want to comment out more than one line you can use block comments.
Block comment starts with slash-asterisk */* and includes all the text before first asterisk-slash */*. Block comment is not limited by one line and gives you power of making a note in absolutely any place in code.
Of course this example is ridiculous! But it clearly shows the power of block comment. Feel free to comment anywhere!