What are the uses of custom labels in Salesforce?

Hello Chanchal

Custom labels are custom text values that can be accessed from Apex classes or Visualforce pages. The values can be translated into any language Salesforce supports. Custom labels enable developers to create multilingual applications by automatically presenting information (for example, help text or error messages) in a user’s native language.
You can create up to 5,000 custom labels for your organization, and they can be up to 1,000 characters in length.

To access custom labels, Go To Setup — Create — Custom Labels. Click on New Custom Labels.Enter value for name, value and description. We can use custom label name to access custom label value in apex code using System.Label.labelName

The advantage of using custom label is that label will be displayed to user depending on their language automatically.

Thanks.