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## Does JavaScript have double?

**JavaScript numbers are always stored as double precision floating point numbers**, following the international IEEE 754 standard.

## Is float in JavaScript?

Usually we check types in javascript by using typeOf method but **javascript doesn’t support float type** so it return a Number when you check a type of float number.

## What is not not in JS?

The JavaScript Not Operator (!)

operator **reverses the logical (true or false) state of the value**. In this case it is the truthy or falsey value. This may seem odd, but it can be useful.

## What is an integer in JavaScript?

In JavaScript, all numbers are floating point. Integers **are floating-point numbers without a fraction**. Converting a number n to an integer means finding the integer that is “closest” to n (where the meaning of “closest” depends on how you convert).

## What is the maximum number in JavaScript?

The MAX_VALUE property returns the largest number possible in JavaScript. This static property has a value of **1.7976931348623157e+308**. Note: Numbers larger than MAX_VALUE are represented as infinity.

## What is == and === in JavaScript?

= is **used for assigning values to a variable** in JavaScript. == is used for comparison between two variables irrespective of the datatype of variable. === is used for comparision between two variables but this will check strict type, which means it will check datatype and compare two values.

## Is NaN in JavaScript?

JavaScript Number isNaN()

isNaN() method determines whether a value is NaN (**Not-A-Number**). This method returns true if the value is of the type Number, and equates to NaN. Otherwise it returns false. … isNaN() does not convert the values to a Number, and will not return true for any value that is not of the type Number.

## What is null JavaScript?

JavaScript null is a primitive type that contains a special value null . JavaScript uses the null value to **represent the intentional absence of any object value**. If you find a variable or a function that returns null , it means that the expected object couldn’t be created.

## How many types of JavaScript are there?

In Javascript, there are **five basic**, or primitive, types of data. The five most basic types of data are strings, numbers, booleans, undefined, and null.

## What is not in Java?

The not operator is **a logical operator**, represented in Java by the ! … It’s a unary operator that takes a boolean value as its operand. The not operator works by inverting (or negating) the value of its operand.

## What does two mean in JavaScript?

If you have ever noticed a double exclamation mark (!!) in someone’s JavaScript code you may be curious what it’s for and what it does. It’s really simple: **it’s short way to cast a variable to be a boolean (true or false) value**.

## What is three dots in JS?

(three dots in JavaScript) is called **the Spread Syntax or Spread Operator**. This allows an iterable such as an array expression or string to be expanded or an object expression to be expanded wherever placed. This is not specific to React. It is a JavaScript operator.

## Is C++ integer or float?

7 Answers. Read from cin into a string and then check the string for the presence of a decimal point. If there is a decimal point, call atof() on the string to convert it to a **float**, otherwise call atoi() to convert it to an integer.

## Is number in TypeScript?

Just like JavaScript, TypeScript supports number data type. **All numbers are stored** as floating point numbers. These numbers can be Decimal (base 10), Hexadecimal (base 16) or Octal (base 8). In the above example, let first:number = 1; stores a positive integer as a number.

## Is Infinity a JS?

JavaScript isFinite() Function

The isFinite() function determines whether a number is a finite, legal number. This function returns false if the value is +infinity, -infinity, or NaN (Not-a-Number), otherwise it returns true.