Heartbleed, the bug being called one of the Internet's biggest security threats, has been around for two years -- but it was only recently discovered. While many companies have released patches, your information is still vulnerable; but between our handy chart of which passwords you need to change and our explainer video, above, we've got you covered from all sides.
The latest video in our Mashable Explains series gives you the low down on how Heartbleed works, why you should take it seriously and what you can do to protect your information.
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Previously on Mashable Explains: What Is the Deep Web?