What is a price gap and how does it equate to price action

A gap in price is easily identified as thin liquidity, thin liquidity is price moving strongly in one direction causing an imbalance in price action. We as traders can use specific levels identifying where the critical levels are prior to the thin liquidity being generated. IE we move back in time to analyse where price will first want to fill in the imbalance in price. Knowing where these levels are and come from gives us bias into these known levels once price tips it's hand for the reversal, then we can wait till the timing is right on the specific day and set our risk to reward accordingly.