Lawn aeration is the process of creating air channels in your lawn so that air can freely pass into the soil and circulate around the grass roots. This aeration is achieved by either:

A) Removing small cylinder shaped cores about 0.5cm wide and 5-10cm deep (similar to the idea of coring an apple), this is known as core aeration.

B) Creating aeration channels by inserting solid spikes (such as the tines of a garden fork) into the soil.