JavaScript for Beginners - Basic Concepts (Data Types) (P: VI)

 

Data Types

The term data type refers to the types of values with which a program can work. JavaScript variables can hold many data types, such as numbers, strings, arrays and many more.

Unlike many other programming languages, JavaScript dose not define different types of numbers like integers, short, long, floating-point, etc.

Numbers

JavaScript numbers can be written with or without decimals.

JavaScript numbers can also have decimals

Result:

Note: JavaScript numbers are always stored as double precision floating point numbers.

Strings

JavaScript strings are used for storing and manipulating text.

A string can be any text that appears within quotes. You can single or double quotes.

 You can use quotes inside a string as they don’t match the quotes surrounding the string.

As strings, must be written within quotes, quotes inside the string must be handled. The backslash (\) escape character turns special characters into string characters.

Result:

Note: If you begin a string with a single quote, then you should also end it with a single quote. The same rule applies to double quotes. Otherwise, JavaScript will become confused.

The escape character (\) can also be used to insert other special characters into a string. These special characters can be added to a text string using the backslash sign

Code	Outputs
\’	Single Quote
\”	Double quote
\\	Backslash
\n	New line
\r	Carriage return
\t	Tab
\b	Backspace
\f	Form end

Boolean

In JavaScript boolean, you can have one of two values, either true of false. These are useful when you need a data type that can only have one of two values such as Yes/No, On/Off, True/False.

Example

Note: The boolean value of 0 (zero), null, undefined, empty string is false. Everything with a real value is true