Pretty good, but here is an explanation in plainer english.

Fuel and air is mixed in the combustion chamber. Piston approaches TDC (top dead centre), compressing the mixture. Spark plug ignites mixture, just before TDC (to give it time to light up the charge). The mixture burns, it doesn't explode. As it burns, the flame front moves from the spark plug out to the cylinder walls. The mixture expands, thus driving down the piston on the power stroke. All this is in an ideal situation.

Two different problems can occur (well, actually, lots of problems, but here are two):

As the flame front moves out, heating the remaining mixture, the mixture can explode instead of burning (due to the heat, and in advance of the flame front). That is pinging. It creates a metallic, hollow sound, a little like rocks being shaken in a steel can. It can be reduced (prevented) with higher octane fuel (more resistant to ignition), lower temperatures, better combustion chamber design, etc. Very heavy pinging can produce a knocking sound.

Pre-ignition occurs when a hot spot ignites the mixture before the spark plug does. It can occur from pieces of carbon in the combustion chamber that glow very hot, and act as an ignition source. Pre-ignition is any condition whereby the mixture ignites before it is supposed to. Pre-ignition can lead to pinging, and pinging can indicate pre-ignition, they are related, but different.

Hope this helps.

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