What is an SSL certificate?
The thing that puts the padlock and the "https" in your address. It encrypts data between your site and its visitors.
An SSL certificate (more accurately TLS these days) is what enables the secure, encrypted connection between your website and the people visiting it: the padlock icon and the https:// at the start of your address.
What it actually does
It encrypts the data travelling between a visitor’s browser and your server, so things like contact-form details or passwords can’t be read in transit. It also confirms that visitors are connecting to the real you, not an impostor.
Why every site needs one
- Trust. Browsers flag sites without it as “Not secure”, a quiet conversion-killer.
- SEO. HTTPS is a confirmed (if small) Google ranking signal; see SEO.
- Function. Many modern browser features simply won’t run without it.
The good news
SSL certificates are now usually free and automatic. Most modern hosting issues and renews them for you via services like Let’s Encrypt. There’s no longer any excuse for a site to be served insecurely. If yours shows “Not secure,” that’s worth fixing today.