What is the use of aura:id in Salesforce lightning component?

Hi Laveena,

You can retrieve a component using its local ID in your JavaScript code. A local ID is an ID that is only scoped to the component. A local ID is often unique but it’s not required to be unique. Local ID is created by the aura:id attribute.

For Example:

<lightning:button aura:id="button1" label="button1"/>

Find the button component by calling cmp.find("button1") in your client-side controller, where cmp is a reference to the component containing the button.

find() returns different types depending on the result.

• If the local ID is unique, find() returns the component.
• If there are multiple components with the same local ID, find() returns an array of the components.
• If there is no matching local ID, find() returns undefined.