Back in 2012, David Emm, Senior Security Researcher at Kaspersky Lab, was explaining what is collectively called as malware.
He begins by making the distinction of some of the most common threats that come under the umbrella of malware, which are viruses, worms, and trojans. While all of them are qualified as malware, the scope and the mechanism of action of each is quite different.
Since then, malware such as ransomware has began spreading like wildfire on the Internet, the boom of cryptocurrencies allowing for relatively stealthy collection of ransoms to release infected and encrypted information. Anyhow, that's the subject of another video.
If you watch this one, you will be more prepared in facing what we are all exposed to (an ocean of online threats) which will also make you better able to protect and overcome such threats.
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Cristi Vlad Self-Experimenter and Author