33 lines
1.0 KiB
Markdown
33 lines
1.0 KiB
Markdown
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---
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title: Declare JavaScript Variables
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---
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# Declare JavaScript Variables
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When we store data in a data structure, we call it a variable. JavaScript variables are written in camel case. An example of camel case is: `camelCase`.
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You can declare a variable this way
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```js
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var myName = "Rafael";
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```
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ES6 introduced two other ways to declare variables. __let__ and __const__. _Let_ is pretty similar to var and for the most part is interchangeable:
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```js
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let myAge = 36;
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```
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Where _let_ differs, is in its scope. When we declare using _var_, it's global in scope. When we declare using _let_, the scope is limited to that function. If you want to use a _let_ variable outside a function, you have to make it global in scope or redeclare it in the next function.
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__const__, on the other hand, can only be declared once. Its value can never change.
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```js
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const myName = "Christina";
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```
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