Sending e-mail with attachments

You can attach any type of file to your e-mail message by setting options as shown in the following code. The following code attaches the active spreadsheet's left-most Sheet content as PDF.

function sendEmailWithAttachments(){
  var file = SpreadsheetApp.getActiveSpreadsheet()
      .getAs(MimeType.PDF);

  // MailApp.sendEmail(recipient, subject, body, options)
  MailApp.sendEmail(
    "[[ Recipient email id ]]",
    "Chapter 3",
    "",
    {
      attachments: [file],
      name: 'Chapter 3 test attachment'
    }
  );

}