A Note on Privacy
A simple tip: don’t put anything in an email that you wouldn’t put in letter. You know that both business and personal letters can be lost or shown to someone else. The same rules and ethics should apply to email and other forms of electronic correspondence.
Should companies be monitoring their employees’ email? I don’t think they should, but it’s become standard practice for many companies. Plus in government, there are nearly 630 agencies in the UK alone that have access to all your emails and other electronic communications (including mobile telephony) and keep them for 12 months. (Info about this here, here and here)/ So you really need to be aware of the fact that you are being watched, and that in many ways privacy doesn’t exist anymore. It’s up to you to know the consequences of using technology.

