# Advanced Custom Fields

Advanced Custom Fields is a WordPress plugin that expands the versitility of the Wordpress's inherit Content Management System.

Our primarily job as developers is make it easy for clients to enter their own data and have it render to the view, or manipulated the data to meet satisfy their business logic.

We create advanced custom fields, they enter data, we take their input, and render to the website.

This is ideally a beautiful, simple, and flexible system, with a simple PHP API to register new data objects with just a few lines of code. However there are several caveats to ACF.

ACF's and their metadata are stored in JSON format, in the acf-json folder.

# Syncing ACF

Synchronized JSON is a feature which detects changes to local JSON files and allows the user to update the corresponding field groups within the Database.

JSON field groups are determined ‘available for sync’ when either the JSON field group does not exist in the DB (field group key is used to match pair), or when the JSON field group contains a higher ‘modified’ value than the DB post’s modified date.