> ## Documentation Index
> Fetch the complete documentation index at: https://plivo.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Voice Notification

> Send audio notifications via voice calls with text-to-speech or recordings

## Overview

This guide shows how to send audio notifications using voice calls. You can play recorded audio when the call recipient answers or use text-to-speech, as we show here, combining static text with dynamic information that Plivo gets from a variable.

You can use voice notification for use cases such as:

* Order notification
* Booking status
* Delivery status
* Flight cancellation/rescheduling
* Two-factor authentication/one-time password
* New offer notification
* Account balance notification

Implement voice notification either by using our PHLO visual workflow builder or our APIs and XML documents. Follow the instructions in one of the tabs below.

<Tabs>
  <Tab title="Using XML">
    Here’s how to use Plivo APIs and XML to implement voice notifications.

    <h2 id="xml-how-it-works"> How it works</h2>

    <Frame>
      <img src="https://mintcdn.com/plivo/GjxgkWYDEc2_LVPj/images/outbound-calls.png?fit=max&auto=format&n=GjxgkWYDEc2_LVPj&q=85&s=f8b62e42991d9fd92d93eab071cb4124" alt="Outbound Call Flow" width="1448" height="774" data-path="images/outbound-calls.png" />
    </Frame>

    Plivo requests an answer URL when the call is answered (step 4) and expects the file at that address to hold a valid XML response from the application with instructions on how to handle the call. To see how this works, you can use [https://s3.amazonaws.com/static.plivo.com/notification.xml](https://s3.amazonaws.com/static.plivo.com/notification.xml) as an answer URL to test your first outgoing call. The file contains this XML code:

    ```xml theme={null}
    <Response> 
    <Speak>Congratulations, your order was successfully placed</Speak> 
    </Response>
    ```

    This code instructs Plivo to say, “Congratulations, your order was successfully placed” to the call recipient. You can find the entire list of valid Plivo XML verbs in our [XML Reference](/voice/xml/overview/) documentation.

    <h2 id="xml-prerequisites">Prerequisites</h2>

    To get started, you need a Plivo account —  [sign up](https://cx.plivo.com/signup) with your work email address if you don’t have one already. If this is your first time using Plivo APIs, follow our instructions to [set up a Go development environment](/sdk/server/set-up-go-dev-environment-api-xml-voice/).

    <h2 id="xml-create-a-voice-notification-application-in-go">Create a voice notification application in Go</h2>

    Create a file called `MakeCall.go` and paste into it this code.

    ```go theme={null}
    package main

    import "fmt"
    import "github.com/plivo/plivo-go/v7"

    func main() {
    	client, err := plivo.NewClient("<auth_id>","<auth_token>", &plivo.ClientOptions{})
    	if err != nil {
    			fmt.Print("Error", err.Error())
    			return
    		}
    	response, err := client.Calls.Create(
    		plivo.CallCreateParams{
    			From: "<caller_id>",
    			To: "<destination_number>",
    			AnswerURL: "https://s3.amazonaws.com/static.plivo.com/notification.xml",
    			AnswerMethod: "GET",
    		},
    	)
    	if err != nil {
    			fmt.Print("Error", err.Error())
    			return
    		}
    	fmt.Printf("Response: %#v\n", response)
    }
    ```

    Replace the auth placeholders with your authentication credentials from the [Plivo console](https://cx.plivo.com/home). Replace the phone number placeholders with actual phone numbers in [E.164 format](https://en.wikipedia.org/wiki/E.164) (for example, +12025551234).

    <Note>
      <strong>Note:</strong>
      We recommend that you store your credentials in the `auth_id` and `auth_token` environment variables, to avoid the possibility of accidentally committing them to source control. If you do this, you can initialize the client with no arguments and Plivo will automatically fetch the values from the environment variables. You can use the `os.Setenv` and `os.Getenv` functions to store environment variables and fetch them when initializing the client.
    </Note>

    <h2 id="xml-test">Test</h2>

    Save the file and run it.

    ```shell theme={null}
    go run MakeCall.go
    ```
  </Tab>
</Tabs>