What It Is
PHP is a programming language that runs on the web server. When someone visits a WordPress page, PHP gathers the pieces (your text, images, menu and theme) from the database and assembles them into a page the browser can show. It is a bit like a print shop that fills in a template with your details each time someone asks for a copy. Visitors never see PHP itself, only the finished page.
Why It Matters for Your Business
For a small business, PHP matters mostly because WordPress depends on it. The PHP version on your hosting affects speed and security. Older versions stop receiving security fixes, which leaves a site exposed. A salon running WordPress on an outdated PHP version might see slower booking pages or warnings in the dashboard, even though nothing on the site looks different.
Good to Know
Common mistake: upgrading PHP without testing. Some old plugins or themes break on newer versions. The safe approach is to update plugins first, test the new PHP version on a staging copy of the site, then switch the live site once everything works and you have a fresh backup.