A WordPress update is a new version of your site's software - the WordPress core, a theme, or a plugin. Updates add features and, importantly, patch security holes, which is why keeping them current matters so much.
Also known as: Core update, plugin update, version update
In plain English
WordPress, your theme, and every plugin are software that releases new versions. Updates fix bugs, add features, and - critically - patch security vulnerabilities that attackers actively exploit.
Why it matters for your business
Running outdated software is the leading cause of WordPress hacks - known vulnerabilities are public, and bots scan for sites running them. But updates can also break things, which is why they should be tested (staging) and backed up first.
When you'll run into it
WordPress core updates are frequent and automatic for minor versions; plugins and themes update whenever their authors release fixes. The discipline is testing before applying.
Run into this on your site?
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