JavaScript, like any other programming language, relies on data types to organize and manipulate information. These data types define the kind of values a variable can hold.
- Arrays: Ordered collections of items, similar to lists. Each item has an index (numerical position) for access. Arrays can hold elements of any data type, even mixed types.
- Objects: These are complex collections of key-value pairs, where keys (often strings) are used to access values which can be of any data type, including other objects. Think of them as digital dictionaries storing information.
- Numbers: These represent numeric values, including integers (whole numbers) and decimals (floating-point numbers). They can also handle special values like Infinity (extremely large number) and NaN (Not a Number).
- Strings: Strings represent sequences of characters, used for text data enclosed in quotes (either single or double).
- Booleans: These are the simplest, holding only logical values: true or false. They are often used for conditional statements.
- Undefined: This indicates a variable that has been declared but not yet assigned a value.
- Null: Represents the intentional absence of a value. It’s different from undefined as it’s an explicit assignment.
Selecting the appropriate data type keeps your code clean and efficient, hence the reason why TypeScript came into play and also the reason why developers are switching to Typescript. Numbers are perfect for calculations, strings for text, booleans for logical checks, and objects/arrays for storing and organizing complex data.