Custom Fields
- David Hayes. How to Create and Use WordPress Custom Fields. wpshout, 2019.
- Daniel Pataki. Creating Custom Fields Manually in WordPress. wpmudev, 2016.
- Josh Pollock. Adding Custom Fields to WordPress Programmatically. envatotuts, 2014.
- William Craig. Enhancing WordPress Custom Fields with Search Filtering. webfx.
- Josh Pollock. Using the WordPress Custom Field User Interface. envatotuts, 2014.
- Rachel McCollin. WordPress Development for Intermediate Users: Custom Fields and Metadata. wpmudev, 2016.
Meta Boxes
- Narayan Prusty. Adding Custom Meta Boxes to the WordPress Admin Interface. sitepoint, 2015.
- Collins Agbonghama. Adding Meta Boxes to Post Types in WordPress. sitepoint, 2017.
- Carlo Daniele. Creating Custom Post Meta Boxes in WordPress. wpmudev, 2017.
- Tom McFarlin. Creating Maintainable WordPress Meta Boxes Series. envatotuts, 2014.
- Part 1.
- Part 2: The Layout.
- Part 3: The Front-End.
- Part 4: Finish the Front-End.
- Part 5: Verify and Sanitize.
- Part 6: Save and Retrieve.
- Part 7: Refactoring.
- WordPress Meta Boxes: A Comprehensive Developer’s Guide. Theme Foundation, 2013.
- Tom McFarlin. Two Ways to Save Meta Box Data in WordPress. 2014.
- Tom McFarlin. WordPress Meta Boxes. 2014.
Meta Data
- Fred Meyer. How to Create and Use WordPress User Metadata (User Meta). wpshout, 2019.
- Josh Pollock. Mastering WordPress Meta Data Series. envatotuts, 2014.
- Tom McFarlin. WordPress Meta Data. 2015.