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What is SSL/TLS? Certificates, explained
SSL — properly called TLS today — is the technology behind the padlock in your browser. It does two jobs at once: it encrypts everything between you and a website so nobody along the way can read it, and it proves the site you reached is really the one you asked for. Both jobs run on a small file called a certificate.
The two jobs: encryption and identity
Encryption is the obvious half: with TLS, a password or credit-card number crossing the network looks like random noise to anyone in between — the café Wi-Fi, the provider, anyone. Without it, that traffic is a postcard anybody en route can read.
Identity is the half people forget: the certificate is a signed statement from a trusted authority that this server is entitled to answer for this domain. That's what stops an attacker from simply pretending to be your bank on an open network.
Where certificates come from
Certificates are issued by certificate authorities — organisations your browser already trusts. The authority checks that whoever requests a certificate actually controls the domain, then signs it, typically for a few months at a time.
The short lifetime is deliberate: certificates that expire and renew automatically limit the damage a stolen key can do. On systems we operate, renewal is automated and monitored — an expired certificate is an outage, and it's an entirely preventable one.
What it means for your business
Browsers now mark plain HTTP pages as "Not secure", search engines rank HTTPS pages ahead of unencrypted ones, and modern browser features — payments, location, camera — simply refuse to run without TLS. A certificate stopped being optional years ago.
Every site and system we deliver ships with TLS configured, renewing automatically, and redirecting insecure traffic — as part of the build, not a line item.
FAQ
Is SSL the same as TLS?
Practically, yes — TLS is the modern protocol that replaced SSL, but the old name stuck. When anyone says "SSL certificate" today, they mean a TLS certificate.
What happens when a certificate expires?
Browsers show a full-page security warning and most visitors leave immediately; APIs and apps refuse to connect. That's why we automate and monitor renewal on every system we run — expiry is an outage you can simply never have.
Do I need to pay for a certificate?
For most websites, no — automated authorities like Let's Encrypt issue certificates free of charge, and they're every bit as secure. Paid certificates mainly buy specific validation levels some organisations require.