TypeScript

// TODO: update this

<script type="text/javascript">
  var a = 5;
</script>

<script src="/externalfile/filename.js"></script>

Data types

// TODO: https://dzone.com/articles/what-are-the-basic-data-types-in-typescript

Data Types	Examples
undefined	A variable that has not been assigned a value is of type undefined.
null	no value.
string	'a', 'aa', 'aaa', 'Hello!', '11 cats'
number	12, -1, 0.4
boolean	true, false
object	A collection of properties.
symbol	Represents a unique identifier.