What countries is Coinbase available in?

Could you please elaborate on the availability of Coinbase in different countries? I'm curious to know which regions have access to this cryptocurrency exchange platform. Could you provide a list of the countries where Coinbase is currently operational? Additionally, are there any restrictions or limitations in certain countries that might affect users' ability to use Coinbase? It would be helpful to understand the global reach and any potential challenges associated with using this service in different parts of the world.