What is it?
This term probably rings a bell with most people, which is normal because the market has used this term for decades, whether or not it is appropriate.

Even to this day, using a seasoned Anti-Virus solution is key.

Although many diverse specialized products exist at the moment, many vendors use this term in order not to confuse an average end-user. We do not want to complicate the matter, but wish to inform the studious user with (substantiated) information, in which case some jargon is unavoidable.
To give you an idea of the differences between current-day security solutions, we'd like to refer to this article.

Why do I need it?

Basically, you need a good fundamental security solution to cover and protect you against most of the current-day threats. You want to pick the vendor covering the majority of your needs and thereby not slowing down your computer and processes noticeably. Most AV vendors propose their premium product, promising to cover all dangers for you. 

In practice though, cyber criminals are trying to bypass detection of (especially) commonly used AV products. For this fact only, one should consider using an on-demand product providing you with some extra protection. View this as your second opinion product.

More concrete evidence: In the past decades it was somewhat accepted that your Anti-Virus product would not catch all viruses / malware directly. If it disarmed these some time later effectively, an average user would not complain. These days, we see more aggressive malware coming along and causing much more harm right after infection / while becoming active on your computer and before being detected by the Anti-Virus product.

Some examples :                  

• Rootkits : effectively passing your protection
• Ransomware : a great example of current-day threat causing you extreme trouble by encrypting all your precious data and demanding some ransom in order to be able to recover your files. 

These cases are not thoroughly foreseen by Anti-Virus solutions. We advise you to use a bundle of multiple security products wisely. Please have a look at our bundle offer page for the best picks at a fair price.

How to (not) use it?

In practice, we noticed many people installing a selection of AV products on one computer with the thought of having better protection. Despite this seeming a very logical and advisable mindset, you should be aware that you potentially gained a small percentage more of detection (mainly on known threats and signatures), but at the same time have multiple products possibly conflicting on various techniques, leaving you with a sluggish and unstable system. Consider the fact that some vendors share their underlying engine with others, in which case you gain even less going this way. 

So, again, we advise you to pick one great Anti-Virus product and also use a good Anti-Malware / Anti-Exploit product in parallel. That way, every product covers another private area.