I thought that some readers might find this article on "How To Geek" useful.

It describes some simple ways to tell whether your webcam has been hacked, which probably means that someone has been spying on you.

I thought this especially relevant at the moment, given that there currently seems to be a campaign to blackmail people with claims that someone has "recorded some videos of you jerking off to highly controversial adult videos." I am currently receiving several such emails per day with this claim, but they do not fool me.

Not only can you use the article to check whether your webcam has been spying on you, but there are some very simple things you can do to prevent such intrusions:

1. If you have a separate webcam, unplug it when you are not using it;
2. If you have a webcam built into your laptop, cover it (e.g. with a post-it note or a folded small piece of paper) when you are not using it;
3. Make sure that your firewall is on and properly configured;
4. Install a malware/virus checker, and scan your computer with it regularly;
5. Seriously consider changing from Windows (which is very prone to hacking and malware) to Linux or a Mac (both of which are much less prone to such problems);
6. Never respond to emails that seem to be phishing or blackmail attempts;
7. Use some critical thinking when you receiving such emails.