Zoho Creator 5 API documentation

Zoho Creator 5 API documentation

I'm looking for documentation on building API connections w/ third party sites/apps in Creator 5 - I only see documentation for Creator 6 in the Knowledgebase. I'm probably getting in over my head really - I have no experience w/ API or development other than learning Deluge for a few years. But any pointers on how to get started would be appreciated. Thank you.