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Comparison with the Equality Operator

JavaScript Comparison and Logical Operators - Comparison and Logical operators are used to test for true or false. What is boolean in JavaScript? A JavaScript Boolean represents one of two values: true or false. The if Statement - Use the if statement to specify a block of JavaScript code to be executed if a condition is true. A function in JavaScript is similar to a procedure—a set of statements that performs a task or calculates a value, but for a procedure to qualify as a function, it should take some input and return an output where there is some obvious relationship between the input and the output. The return statement is used to return a particular value from the function to the function caller. The function will stop executing when the return statement is called. The return statement should be the last statement in a function because the code after the return statement will be unreachable. Type coercion is the process of converting value from one type to another (such as string to number, object to boolean, and so on). Any type, be it primitive or an object, is a valid subject for type coercion. To recall, primitives are: number, string, boolean, null, undefined + Symbol (added in ES6). JavaScript Data Types - String, Number, Bigint, Boolean, Undefined, Null, Symbol, Object. A string is a sequence of one or more characters that may consist of letters, numbers, or symbols. Strings in JavaScript are primitive data types and immutable, which means they are unchanging. The JavaScript Number type is a double-precision 64-bit binary format IEEE 754 value, like double in Java or C#. This means it can represent fractional values, but there are some limits to the stored number's magnitude and precision. JavaScript BigInt variables are used to store big integer values that are too big to be represented by a normal JavaScript Number. 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. A variable that has not been assigned a value is of type undefined . A method or statement also returns undefined if the variable that is being evaluated does not have an assigned value. A function returns undefined if a value was not returned. The null value represents the intentional absence of any object value. It is one of JavaScript's primitive values and is treated as falsy for boolean operations. JavaScript Symbols are a new type of primitive data type introduced in the ES6 version of the language. They are used to represent unique values that can be used as identifiers or keys in objects. They are also used to create private properties and methods in classes. In JavaScript, an object is a standalone entity, with properties and type. Compare it with a cup, for example. A cup is an object, with properties. A cup has a color, a design, weight, a material it is made of, etc. The same way, JavaScript objects can have properties, which define their characteristics. In programming, data types is an important concept. To be able to operate on variables, it is important to know something about the type. Without data types, a computer cannot safely solve this: