Microsoft Word files are a security hazard
Unlike standard data formats, Word files can contain programming code which can be executed by your computer automatically when the document is opened. Microsoft’s reason for including this “feature” in Word was to allow word processing macros to be saved along with the document. However, it was not long before malicious people began exploiting this design flaw by writing Word macro code to surreptitiously delete random files or otherwise damage your computer. As a result, Word files are now notorious as the vector for dozens of computer viruses. When you receive a Word attachment by e-mail, do you really want to take the risk of welcoming a proverbial (and in computing terms, literal) Trojan horse into your system?
Microsoft Word documents are extremely large compared to other file formats
The Word file format is bloated and inefficient; documents are often many orders of magnitude larger than the amount of text they contain. Even in today’s age of ample hard drives, a large collection of Microsoft Word files can quickly eat up available disk space. For the millions of people who use Mobile Internet connection, receiving Word files in e-mail can mean minutes of waiting for the documents to download. Compare this to the mere seconds it would take to transfer the equivalent amount of information as plain text.
Sending Microsoft Word files can violate your privacy
Microsoft Word is often configured by default to automatically track and record changes you make to a document. What many people do not realize is that this record of changes is actually silently embedded in the file every time you save your document. When you send such a document to a third party, it is a trivial matter for them to recover this log and see how the document appeared several revisions ago. Thus compromising or confidential information you thought you removed from a document before sending it may in fact still be accessible to the recipient. Indeed, there have been at least a few high-profile cases of confidential information being leaked via publically-posted Word documents.
