Is OKX free?

I've been hearing a lot about OKX recently, and I'm curious about whether it's free to use or not. Could you please clarify this for me? I understand that it's a cryptocurrency exchange platform, but does that mean there are no costs involved in using its services? Or are there certain fees that I should be aware of? It would be great if you could break down the costs, if any, associated with OKX, so that I can make an informed decision about whether to use it or not. Thank you for your help in clarifying this matter.