The variable is used to store values in it. In order to give names to any variable it's recommended to give a meaningful name.
<h4 id="heading-declaring-variable">Declaring Variable</h4>
<pre><code class="lang-javascript">let message; // declaring a variable
</code></pre>
Once any variable is been declared we need in initialize that variable.
For Example,
<pre><code class="lang-javascript">message = "Good Morning"
</code></pre>
We can also initialise and declare a variable at the same time.
<pre><code class="lang-javascript">let message = "hello"
</code></pre>
There are set of rules define defined in javascript which must be followed when variable name convention is given:
<ol>
<li>variable names must not be reserved keywords like <code>function</code> , <code>let</code>, <code>var</code> const and many more.
</li>
<li>variable must not start with numeric values like <code>123message</code> , <code>3.14PI</code> .
</li>
<li>variables are case-sensitive. That means <code>message</code> , <code>Message</code> both are different.
</li>
<li>the variable must contain letters, numbers, an alphanumeric set of characters, <code>_</code> and <code>$</code> and it can't be separated by spaces.
</li>
</ol>

The variable is used to store values in it. In order to give names to any variable it's recommended to give a **meaningful name**.

#### Declaring Variable

```javascript
let message; // declaring a variable
```

Once any variable is been declared we need in initialize that variable.

For Example,

```javascript
message = "Good Morning"
```

We can also initialise and declare a variable at the same time.

```javascript
let message = "hello"
```

There are set of rules define defined in javascript which must be followed when variable name convention is given:

1. variable names must not be reserved keywords like `function` , `let`, `var` const and many more.
    
2. variable must not start with numeric values like `123message` , `3.14PI` .
    
3. variables are case-sensitive. That means `message` , `Message` both are different.
    
4. the variable must contain letters, numbers, an alphanumeric set of characters, `_` and `$` and it can't be separated by spaces.