External API call from wordpress client (javascript) possible?

I was just wondering, would it be possible to make calls to an external API such as Yelp, in wordpress, but using javascript on the client side and not on the server in php? Has done something like this before and could possibly refer me somewhere?

I am able to talk to the API in javascript but am struggling to do the same in PHP, hence the question.

Would appreciate any advice.

via Chebli Mohamed