What is the fee on a swap?

Excuse me, could you please elaborate on the fee structure associated with a swap transaction in the world of cryptocurrency and finance? I'm particularly interested in understanding the different types of fees that might be incurred, such as those imposed by exchanges, network fees, or any additional charges that might be levied by third-party service providers. Additionally, I'd like to know if these fees are static or subject to variation based on factors like market conditions or the specific swap being executed. Thank you for your assistance in clarifying this matter.