Sometimes, you may need to prevent a specific part of your code from executing. Deleting the entire code isn't convenient if you want to test a separate section later. There are various scenarios where you may need to temporarily halt the execution of a non-working part of your code. In such cases, comments come to your rescue.

Note

Comments provide a syntax for hiding sections of your code from the interpreter or compiler. They are also valuable for documenting code for other developers.

Single-line Comments

Single-line comments block the entire line of code, ensuring that the code above and below them is executed. The syntax for single-line comments is straightforward: you need to add // before the code on the line you wish to comment out:

The example above shows that the comment // blocks the second code line, which is not executed.

We can also use single-line comments to block multiple lines of code in a row:

Also, we can add the comment at the end of the line.

Multi-line Comments

Consider a situation with a large code block, 299 lines long. Commenting each line individually would be time-consuming. That's where multi-line comments come in handy.

Multi-line comments start with /* and end with */. Any code enclosed within them is commented out:

In the example above, we can see that code line from 3 to 10 hasn't been executed.

We can use multi-line comments to comment a part of the line: