# Mailer

### Installation

```shell
composer require sonsofphp/mailer-contract
```

### Definitions

* **Message** - The email message that will be sent.
* **Mailer** - Primary API used to send *messages*.
* **Transport** - Transports are what will actually send the message. This could be SMTP, Null, SendGrid, Amazon SES, or anything like that.
* **Middleware** - Before the message is sent to the transport to be sent, various middlewares have the ability to modify the message.