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Undefined | Data Types and Variables
Introduction to JavaScript (staging)
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Conteúdo do Curso

Introduction to JavaScript (staging)

Introduction to JavaScript (staging)

1. Introduction
2. JavaScript syntax
3. Data Types and Variables

Undefined

What is Undefined

Undefined is also a data type in JavaScript just like the null. When a variable is created or declared without assigning any value to it, then the value of the variable will be set as undefined by default.

12
let age; console.log(age);
copy

Tarefa

Declare a variable numberOfItems and assign the value of undefined to the variable and show the value of the variable.

Tarefa

Declare a variable numberOfItems and assign the value of undefined to the variable and show the value of the variable.

So, undefined variables can also be declared using the undefined keyword.

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Seção 3. Capítulo 31
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Undefined

What is Undefined

Undefined is also a data type in JavaScript just like the null. When a variable is created or declared without assigning any value to it, then the value of the variable will be set as undefined by default.

12
let age; console.log(age);
copy

Tarefa

Declare a variable numberOfItems and assign the value of undefined to the variable and show the value of the variable.

Tarefa

Declare a variable numberOfItems and assign the value of undefined to the variable and show the value of the variable.

So, undefined variables can also be declared using the undefined keyword.

Mude para o desktop para praticar no mundo realContinue de onde você está usando uma das opções abaixo

Tudo estava claro?

Seção 3. Capítulo 31
toggle bottom row

Undefined

What is Undefined

Undefined is also a data type in JavaScript just like the null. When a variable is created or declared without assigning any value to it, then the value of the variable will be set as undefined by default.

12
let age; console.log(age);
copy

Tarefa

Declare a variable numberOfItems and assign the value of undefined to the variable and show the value of the variable.

Tarefa

Declare a variable numberOfItems and assign the value of undefined to the variable and show the value of the variable.

So, undefined variables can also be declared using the undefined keyword.

Mude para o desktop para praticar no mundo realContinue de onde você está usando uma das opções abaixo

Tudo estava claro?

What is Undefined

Undefined is also a data type in JavaScript just like the null. When a variable is created or declared without assigning any value to it, then the value of the variable will be set as undefined by default.

12
let age; console.log(age);
copy

Tarefa

Declare a variable numberOfItems and assign the value of undefined to the variable and show the value of the variable.

So, undefined variables can also be declared using the undefined keyword.

Mude para o desktop para praticar no mundo realContinue de onde você está usando uma das opções abaixo
Seção 3. Capítulo 31
Mude para o desktop para praticar no mundo realContinue de onde você está usando uma das opções abaixo
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