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Why do we need getter in LWC?

 LWC template/component does not allow expression or any manipulation or array expression. To solve this problem "Getter" is solution. It atomically bind data from Java scripts to template.

Error = Invalid expression {employee[0]} - LWC1038: Template expression doesn't allow computed property accesslwc

 <div class="slds-m-around_medium">
           {employee[0]}
<p> The sum of {num1} and {num2} is {num1+num2}
 </div>

Component code
<template>
    <lightning-card title="Getters in LWC">
        <div class="slds-m-around_medium">
            {firstEmployee}
            <p> The sum of {num1} and {num2} is {sumResults}</p>
        </div>
    </lightning-card>
</template>

Java script code
When employee gets updated then automatically firstemployee getter called and updated value will be reflected in component.
import { LightningElement } from 'lwc';

export default class HelloWorld1 extends LightningElement {
   
    num1 = 10;
    num2 = 20;
    employee = ["Asish","behera","Ipsheeta"]
    get firstEmployee(){
        return this.employee[0].toUpperCase();
    }
    get sumResults(){
        return this.num1+this.num2;
    }
   
}

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