An SSL certificate is what puts the padlock and 'https' in your web address. It encrypts the connection between your site and its visitors, and it's why browsers do - or do not - label your site as secure.
Also known as: HTTPS certificate, TLS certificate, security certificate
In plain English
An SSL certificate scrambles the information traveling between your website and the people visiting it, so it cannot be read if it is intercepted. When your site has a valid certificate, the address starts with "https" and the browser shows a padlock. When it does not, browsers warn visitors that the site is "Not Secure."
Why it matters for your business
Two reasons. First, trust: a "Not Secure" label in the address bar makes people hesitate to enter a contact form, let alone make a purchase. Second, Google prefers secure sites and can rank insecure sites lower. An expired or missing certificate can quietly cost you customers and search visibility.
When you'll run into it
Setting up a new site, changing hosts, or the morning a certificate silently expires and visitors start seeing warnings. Certificates renew on a schedule - the job is making sure renewal happens before the certificate lapses.
Run into this on your site?
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