An attachment is a computer file or files place inside an email message. To attach a document to an email message drag the file attachment to the body of the message and drop it. An attachment can also be added by choosing File Attachment from the menu. Most modern email programs place a button on the Toolbar usually in the shape of a paper clip that you can click. A dialog box will open that allows you to browse and select the file that you want to attach. You can attach more than one file to a single email message. Don't move the original document until the message has been sent.
The attached file must be loaded into a program to be viewed. If the attached document was originally created in MS Word you need MS Word on your computer to work with the document. When sending an attachment you should think about whether the intended recipient has the same program on their computer