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Introduction to JavaScript
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Contenido del Curso

Introduction to JavaScript

Introduction to JavaScript

1. Introduction
Writing our first codeOutput Using Variables 1/2Output Using Variables 2/2
2. JavaScript syntax
JavaScript SyntaxJavaScript VariablesJavaScript OperatorsIdentifiers in JavaScriptNaming IdentifiersReserved keywords in JavaScriptNaming Convention in JavaScript. Case StylesVariables Naming ConventionBoolean Naming ConventionConstant Naming ConventionFunction & Classes Naming ConventionMultiline StringsMultiline Strings. ConcatenatingCommenting in JavaScriptCommenting in JavaScript. Multi-line Comments
3. Data Types and Variables
What are Variables?What are Data-types?JavaScript and Type ConversionVar 1/3Var 2/3Var 3/3Let 1/2Let 2/2Constant 1/3Constant 2/3Constant 3/3Number 1/3Number 2/3Number 3/3Boolean 1/4Boolean 2/4Boolean 3/4Boolean 4/4Strings 1/5Strings 2/5Strings 3/5Strings 4/5Strings 5/5BigInt 1/3BigInt 2/3BigInt 3/3Symbols 1/3Symbols 2/3Symbols 3/3NullUndefinedNull vs Undefined

book
Var 3/3

Why var is not used now

Due to hoisting and the global scope declaring variables with the var leads to so much confusion in the code. If we change the value of a variable at just one place intentionally the var will change that value all over the code. It will create so many unexpected results in our code.

Tarea

Swipe to start coding

Hoisting is used in the following code and this code does not give any error but not a preferable approach. Your task is, using only the let keyword, to re-arrange the variables in the code and display all the variables.

Solución

Summary:

  • The var is an alternative to the let keyword in JavaScript.
  • Variables declared with var can be accessed before the declaration.
  • The let and const do not allow hoisting but var does.
  • It is not a good practice to use var instead we should use let.

Switch to desktopCambia al escritorio para practicar en el mundo realContinúe desde donde se encuentra utilizando una de las siguientes opciones
¿Todo estuvo claro?

¿Cómo podemos mejorarlo?

¡Gracias por tus comentarios!

Sección 3. Capítulo 6
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book
Var 3/3

Why var is not used now

Due to hoisting and the global scope declaring variables with the var leads to so much confusion in the code. If we change the value of a variable at just one place intentionally the var will change that value all over the code. It will create so many unexpected results in our code.

Tarea

Swipe to start coding

Hoisting is used in the following code and this code does not give any error but not a preferable approach. Your task is, using only the let keyword, to re-arrange the variables in the code and display all the variables.

Solución

Summary:

  • The var is an alternative to the let keyword in JavaScript.
  • Variables declared with var can be accessed before the declaration.
  • The let and const do not allow hoisting but var does.
  • It is not a good practice to use var instead we should use let.

Switch to desktopCambia al escritorio para practicar en el mundo realContinúe desde donde se encuentra utilizando una de las siguientes opciones
¿Todo estuvo claro?

¿Cómo podemos mejorarlo?

¡Gracias por tus comentarios!

Sección 3. Capítulo 6
Switch to desktopCambia al escritorio para practicar en el mundo realContinúe desde donde se encuentra utilizando una de las siguientes opciones
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