Implied volatility is one of the key determining factors in an option's value. Higher volatility equals higher price. During a normal, slowly grinding market, implied volatility is of less concern when trading options, because it won't fluctuate much, but in times of extreme market moves, implied volatility can be the difference in whether or not an option trade is profitable or not.

Think of implied volatility this way:

Let's say KO (Coca-Cola) stock is trading at $50. An option put buyer comes along and says, "Hey, I'll buy a $40 put from you, expiring in a month, and I'll pay you $1 for it."

During normal market conditions you might say, "Sure, I'll sell you that." because you are fairly confident that during normal market conditions it is unlikely that KO stock would drop 20% in just one month. It's an old established company that doesn't make moves that large very often. It would be a pretty safe bet.

But what if the coronavirus market hit and stocks were going crazy up and down every day. Now that same put buyer comes along and offers you $1 for the $40 put expiring in one month. Would you still sell it to him at the same price? Of course not, right? Because the market is more volatile now you would require him to pay you more for accepting the risk. You might charge him $3 for that put under these circumstances.

That's implied volatility. As the perceived risk (implied volatility) increases, the price of the option increases. As the implied volatility decreases, the price of the option decreases. Higher risk requires higher premium. Lower risk demands less premium.