What countries does Coinbase serve?

Good day, I'm curious about the global reach of Coinbase, a leading cryptocurrency exchange platform. I'm particularly interested in knowing which countries Coinbase serves, as I'm considering using their services for my own cryptocurrency transactions. Are there any restrictions or limitations in terms of the countries they operate in? I would appreciate a comprehensive and up-to-date list of the countries Coinbase serves, along with any relevant information regarding any potential barriers or regulations that might affect users from different countries. Thank you in advance for your assistance.