In JavaScript, Semicolons are optional. Simple statements in JavaScript are generally followed by a semicolon character, just as they are in C, C++, and Java. JavaScript, however, allows you to omit this semicolon if each of your statements is placed on a separate line. It is a good programming practice to use semicolons.
For example, the following code could be written without semicolon.
<script> <!-- a = 5 b = 10 //--> </script>
But when formatted in a single line as follows, you must use semicolons −
<script> <!-- a = 5; b = 10; //--> </script>