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Yes, and yes.

Here is an example with GDAX:

Here is an example of an API supporting public access through Gemini:

Here is another (clunkier) one from Kraken:

Usually there’s a UI accessible with an account and an API that allows faster, direct access to the feed.

Thanks. Is there a page that explains how to read that data?

There are more APIs there, publically accessible, small rate limit, have fun.

GDAX == Coinbase API. Trading on Coinbase makes, AFAIK, a market buy/sell through GDAX.

Yes.