PHP workers are background processes that execute PHP code on a server. They are responsible for generating the HTML pages that your website visitors see, as well as handling other tasks such as processing background jobs and sending emails.
The number of PHP workers you need will depend on the amount of traffic your website receives and the complexity of your PHP code. If you have a low-traffic website with simple PHP code, you may only need a few PHP workers. However, if you have a high-traffic website with complex PHP code, you may need dozens or even hundreds of PHP workers.
When a visitor loads your website, their request is assigned to a PHP worker. The worker then executes the necessary PHP code to generate the requested page and send it back to the visitor.
You can read more about PHP workers in our Help center.