What is the circulating supply and demand?

Excuse me, could you please explain what is meant by the "circulating supply and demand" in the context of cryptocurrency? I'm curious to understand how this concept impacts the market value and trading dynamics of digital currencies. Specifically, how is the circulating supply determined, and how does it interact with demand to influence price movements? Additionally, are there any factors that can significantly alter the circulating supply, and what implications does this have for investors and traders? Thank you for your time and expertise.