It is always a good idea to password protect your documents, especially when they contain sensitive information. This short video clip explains how to do that with a Microsoft Office Word document.
A good habit to form when choosing a good password is to never use the same password for multiple sites or documents.
One of my favorite tools to use is LastPass (they have a free and paid versions). It allows you to remember one password for all your passwords. This service is extremely secure and allows a central location for all your access passwords. Needless to say, make sure that your password is very hard to guess but easy enough for you to remember – no English language words you can find in a dictionary.