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Hello friends, nice to see you back.

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In this tutorial we are going to learn about symbol.

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We already know about data type in JavaScript.

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Specially we have seven type of data type string, number, boolean, array, object, null and undefined.

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But a new data type has been added to this list which is symbol.

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And in this video we are going to learn about symbol.

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But before we learn about symbol, let's take a overview to our old data types.

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Suppose I have a variable name a and if we assign this variable and insert the double quotes or single

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quotes, if I provide any value, then we call it a string and it doesn't matter.

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Is it alphabetic or numeric?

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It's mean.

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A data type is string.

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Similarly, if we assign a numeric value without quotes, then we call it number data type.

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But if I provide true or false without quotation, it's mean.

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It's a boolean data type.

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But if I add multiple value in our A variable, then we can use array data type.

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For this we need to use square braces.

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And then we can use multiple value.

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But if I want to add key and value pair then we can use object data type.

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And if I assign null to this variable then we call it null data type.

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And if we do not define any value to this variable in that case we can call it undefined.

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I know if you are in this course, you already know about it, just want to revise once again.

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But in this video we are going to understand a new data type symbol.

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When you want to use symbol data type, you need to take variable and you need to assign with a symbol

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method.

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And remember this should be capital and we need to use round basis.

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After that and insert this symbol we can place any value.

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It may be numeric value or string value something like that.

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And we call this string symbol identifier or description.

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And it's always a unique value.

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I want to say we cannot assign the same value to other symbol.

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Suppose I take another variable b and I'm going to provide the same value.

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As you can see, a and b variable value is same.

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Maybe you can think their value is same.

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So if we try to compare them it returned true.

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But this is not going to happen.

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If we compare this to variable its return false.

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Their value looks same, but they are not same because symbols values are unique and if we try to compare

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it, it returns false when we need to use unique value to our program.

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In that case, we can use symbols.

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So let's start the practical and try to explore more about symbols.