Recently a very serious bug, called the Heartbleed bug, was found in the encryption software that helps secure a lot of the internet’s websites. In theory, the bug could allow an attacker to harvest name/password combos plus other information from sites believed to be safe. It has many people worried and some have even called it one of the biggest security threats the Internet has ever seen.

So what can you do? James Fallows from The Atlantic recently suggested a 5 point checklist:

1) Change passwords for the sites that really matter to you.
2) Do not ever use the same password at two sites that matter to you.
3) Use a password manager.
4) Use “two-step” sign-in.
5) Read more.

If you’re wondering if your favorite website has been affected by the bug, Mashable has compiled a useful list to help in your determination.