FAQs
In JavaScript, a boolean value is one that can either be TRUE or FALSE. If you need to know “yes” or “no” about something, then you would want to use the boolean function. It sounds extremely simple, but booleans are used all the time in JavaScript programming, and they are extremely useful.
What is a boolean in HTML? ›
In HTML, some attributes are boolean attributes, which basically means they can be true or false . They are the case, or they are not the case. They compute to one, or they compute to zero. Examples of these attributes include checked , required , disabled and open .
Is boolean true or false? ›
A Boolean value represents a truth value; that is, TRUE or FALSE.
How to pass boolean value in JavaScript function? ›
The operation can be summarized as follows:
- Booleans are returned as-is.
- undefined turns into false .
- null turns into false .
- 0 , -0 , and NaN turn into false ; other numbers turn into true .
- 0n turns into false ; other BigInts turn into true .
- The empty string "" turns into false ; other strings turn into true .
The Boolean type represents a logical entity and is inhabited by two values: true and false . Boolean values are usually used for conditional operations, including ternary operators, if...else , while , etc.
What are the 3 Boolean operators in JavaScript and how are they used? ›
Logical Operators
| Operator | Description | Example |
|---|
| && | and | (x < 10 && y > 1) is true |
| || | or | (x == 5 || y == 5) is false |
| ! | not | !(x == y) is true |
Boolean expressions are written using Boolean operators (AND) &&, (OR)|| and (NOT) !. Example: 1. (x>1) && (x<5) - returns true if both the conditions are true, i.e if the value of 'x' is between 1 and 5.
What is a Boolean in coding? ›
In computing, the term Boolean means a result that can only have one of two possible values: true or false. Boolean logic takes two statements or expressions and applies a logical operator to generate a Boolean value that can be either true or false. To return the result, operators like AND, OR, NOT, etc. are used.
What is a Boolean example? ›
Boolean operator examples
The following are examples of the Boolean operators in programming: >= – True if a number is greater than or equal to another. <= – True if a number is less than or equal to another. == – True if two values are equivalent.
Is false and false true in Boolean? ›
In Boolean logic, false and false is false. False or false is also false. The negation of false is true.
Boolean Variables and Data Type ( or lack thereof in C )
Zero is used to represent false, and One is used to represent true. For interpretation, Zero is interpreted as false and anything non-zero is interpreted as true.
What is the difference between Boolean and bit? ›
'BIT' vs 'BOOLEAN'
While both 'BIT' and 'BOOLEAN' data types can be used to represent similar kinds of data, they are not interchangeable. 'BIT' can hold 1, 0, or NULL, whereas 'BOOLEAN' holds TRUE, FALSE, or NULL.
What is a JavaScript string? ›
JavaScript String is a sequence of characters, typically used to represent text. It is enclosed in single or double quotes and supports various methods for text manipulation.
What is undefined in JS? ›
Simply put, undefined means a variable has been declared but has not yet been assigned a value. undefined is a type by itself (undefined). Unassigned variables are initialized by JavaScript with a default value of undefined.
What is an object in JS? ›
An object is a collection of properties, and a property is an association between a name (or key) and a value. A property's value can be a function, in which case the property is known as a method. Objects in JavaScript, just as in many other programming languages, can be compared to objects in real life.
What is the function of a Boolean? ›
In computing, the term Boolean means a result that can only have one of two possible values: true or false. Boolean logic takes two statements or expressions and applies a logical operator to generate a Boolean value that can be either true or false. To return the result, operators like AND, OR, NOT, etc.
What is an example of a Boolean in JavaScript? ›
In JavaScript, booleans are the primitive data types that can either be true or false . For example, const a = true; const b = false; Note: If you wrap true or false in a quote, then they are considered as a string.
Is 0 or 1 a Boolean in JavaScript? ›
0 and 1 are type 'number' but in a Boolean expression, 0 casts to false and 1 casts to true . Since a Boolean expression can only ever yield a Boolean, any expression that is not expressly true or false is evaluated in terms of truthy and falsy. Zero is the only number that evaluates to falsy.
What do Boolean variables do? ›
Boolean variables can either be True or False and are stored as 16-bit (2-byte) values. Boolean variables are displayed as either True or False. Like C, when other numeric data types are converted to Boolean values then a 0 becomes False and any other values become True.
