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Dharchini
Dharchini

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Introduction to JavaScript

Javascript is a dynamic computer programming language. It is lightweight and most commonly used as a part of web pages, whose implementations allow client-side script to interact with the user and make dynamic pages. It is an interpreted programming language with object-oriented capabilities.

Advantage

  • Less server interaction
  • Immediate feedback to the visitors
  • Increased interactivity
  • Richer interfaces

Data Types

JavaScript allows you to work with three primitive data types,

  • Numbers, eg. 123, 120.50 etc.
  • Strings of text e.g. "This text string" etc.
  • Boolean e.g. true or false

Variables

Variables are declared with the var keyword as follows. JavaScript is untyped language. This means that a JavaScript variable can hold a value of any data type.

 var name = "Ali";
 var money;
 money = 2000.50;
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JavaScript Variable Scope
The scope of a variable is the region of your program in which it is defined. JavaScript variables have only two scopes.

Global Variables − A global variable has global scope which means it can be defined anywhere in your JavaScript code.

Local Variables − A local variable will be visible only within a function where it is defined. Function parameters are always local to that function.

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Jeff Odhiambo

Congrats @dharchini