WordPress APIs

• Categories API – See below.
• Color Picker API – See below.
• Custom Logo API – See below.
• Dashboard Widgets API
• Database API
• HTTP API
• File Header API
• Filesystem API
• Heartbeat API – See below.
• Metadata API
• Options API
• Pages API – See below.
• Plugin API – See below.
• Quicktags API
• REST API
• Rewrite API
• Settings API
• Shortcode API
• Term Data API – See below.
• Theme Modification API – See below.
• Theme Customization API – See below.
• Transients API
• Widgets API
• XML-RPC WordPress API

Categories API

• Jeremy Heleine. Mastering the WordPress Categories API. sitepoint, 2016.
• Jeremy Heleine. How to List Categories in WordPress Using the Categories API. sitepoint, 2015.

Color Picker API

• Michele Ivani. How to Use WordPress Color Picker API. envatotuts+, 2014.

Custom Logo API

• Jeremy Heleine. How to Use the WordPress Custom Logo API. sitepoint, 2016.

Filesystem API

• Narayan Prusty. An Introduction to the WordPress Filesystem API. sitepoint, 2015.

Heartbeat API

• Tom McFarlin. A Practical Example of the WordPress Heartbeat API. 2014.
• Stephen Harris. Heartbeat API: Using Heartbeat in a Plugin. tutsplus, 2013.
• Pippin Williamson. Using the WordPress Heartbeat API. 2013.

Pages API

• Jeremy Heleine. Understanding WordPress Pages and the Pages API. sitepoint, 2018.

Plugin & Theme API

• Carl Alexander. WordPress for the Adventurous: Plugin API. 2015.
  • Great article that helps one understand how the Plugin API works and how to use it. Gets pretty technical, but Alexander is good at explaining complex concepts.
• Stephen Harris. Interacting with WordPress’ Plug-inin & Theme API. tutsplus, 2012.

Quicktags API

• Baris Unver. A Simple Guide to the WordPress Quicktags API. envatotuts+, 2015.
  • Recommend this one (oops, for right now it is the only one!).

Screen Options API

• Pippin Williamson. Add Screen Options Tab to Your WordPress Plugin. 2012.

Term Data API

• Tom McFarlin. How to Work with WordPress Term Meta: Term Metadata API. tutsplus, 2016.
  • Part of a larger series on term meta.

Theme Modification API

• Tom McFarlin. WordPress Options and Theme Modifications. 2015.
  • Explains why we one would use the theme modification API instead of the options API when creating settings for themes.

Theme Customization API

• Narayan Prusty. Getting Started with the WordPress Theme Customization API. sitepoint, 2015.

Transients API