What It Is
A web application firewall, or WAF, inspects each request a visitor sends to your website and looks for patterns that match known attacks. If a regular firewall is the front desk checking IDs, a WAF is the security guard who also looks inside bags. It can stop tricks such as SQL injection (sneaking database commands into a form) and cross-site scripting (planting harmful code that runs in other visitors’ browsers).
Why It Matters for Your Business
WordPress sites are popular targets because attackers can scan thousands of them for one outdated plugin. A WAF can block many of those attempts even before you have had a chance to update. Picture a bakery whose ordering plugin has a newly announced flaw on a Friday afternoon. A WAF with up-to-date rules may keep the site safe until the update is applied on Monday.
Good to Know
WAFs come in several forms: a service in front of your site (often bundled with a CDN), a feature your host runs on the server, or a WordPress security plugin. Running more than one can cause conflicts or block real customers. If people suddenly report they cannot submit a form, check the WAF logs before assuming the form itself is broken.