Microsoft word’s ability to give away secrets has been known for a long time. It’s possible for people to read the revisions you’ve made to a document unless you are careful. The latest victim to be embarrassed by this trick is the British Government.

Basically, MS Word leaves older text hidden in the document. While you may not be able to see the old text in the document it’s very easy to read many of the changes and who made the changes. It’s important when sending documents to be careful not to give away too much information.

The two biggest villains are the "track changes" and the "fast save" function. Fast save is the most commonly used option, as the name says, it speeds up the saving process by only saving the text that has been changed, leaving the old text hidden in the file. The track changes function lets different users add their comments and review changes to a document.

When a Word document is created with either of these features enabled many of the changes made will be accessible to those with a little computer knowledge. This means all the changes you’ve made to your CV can be found, or the changes made to a job offer can be revealed. In these paranoid times, it’s a good idea to get rid of unnecessary data.

The simplest way is to turn off these features. That is not always feasible or convenient. If it is necessary to use them, use them for the draft documents then turn the feature off and save the document in a new name before sending it.

An even more reliable way is to copy and paste all the text into a new document. As the new document has never had any changes, there is nothing to be exposed in it. Of course, you need to make sure no changes get made afterwards.

Another way is to save the final document in other format. The two most suitable built in Word formats are HTML and Rich Text. In both you will lose some formatting such as tables and layouts.

If formatting is important, then software like Adobe Acrobat is a useful tool. Files created in Acrobat are commonly known as PDFs. A PDF not only strips out redundant data, it also preserves page layouts so the document looks the same on the recipient’s computer as it does on yours.

If you are concerned about the information that might be hidden in your files, take some precautions. Have a policy of only sending out documents that have been freshly saved or send out only in formats that don’t give away secrets. That way you can keep your secrets to yourself.