For example, if you create a file using Word 7.0 for Windows95 and send a copy of that file to someone using WordPerfect 5.0 for Windows, they will not be able to view your file. So, when you are planning to share a file with anyone else, check to see what software they will be using and convert your document to a file format that their software can read. Most popular programs can save files in a variety of formats to facilitate this kind of file sharing. When receiving an attached file, bear in mind that it will, in most cases, not be anything you can view from within your email software. Email software is written to view email messages, not spreadsheets or word processing files.
All email programs indicate, though in different ways, when an incoming message has a file attached.
Some email programs simply display a line of text that shows a file was attached to the message and indicating where on the hard drive the file has been placed. Other email programs display a small window on the screen which actually shows a file icon. Often you'll get a question from your software indicating that it doesn't know what to do with the file.