What is an SSL certificate?
An SSL certificate authenticates a website's identity and enables an encrypted connection between a visitor's browser and the server. The technology evolved from SSL to TLS, though "SSL" remains the common term. A visitor requests a secure page, the server presents its certificate, the browser verifies authenticity, and an encrypted session begins so data travels securely.
Why you can no longer do without it
Security: encryption prevents man-in-the-middle attacks on passwords and banking data, and authentication proves the site is legitimate, preventing identity theft. Business and SEO: HTTPS is a confirmed Google ranking factor, the padlock increases trust and conversions, and it is mandatory for PCI DSS (e-commerce) and GDPR compliance.
Which SSL certificate to choose
Domain Validated (DV): email/DNS verification, minutes to hours, most affordable, fine for personal sites.
Organisation Validated (OV): company verification, 1–3 days, moderate price, for business sites.
Extended Validation (EV): rigorous verification, 1–2 weeks, most expensive (Google removed the special browser display).
Single-domain: protects one domain.
Wildcard: protects all subdomains with one certificate.
Multi-domain (SAN): protects up to 100 different domains.
How to choose for your site type
Personal/blog: Domain Validated, ~£8–40/year (Let's Encrypt or Sectigo).
Business website: Organisation Validated, ~£40–160/year.
E-commerce: Domain Validated is sufficient, ~£8–80/year.
Multiple domains: Wildcard or Multi-Domain, ~£80–240/year.
Installing your SSL certificate
You need hosting that supports SSL, proof of domain ownership, admin access and the certificate files. Installation generally means generating a CSR, submitting the request, installing the certificate files, redirecting HTTP to HTTPS and testing with verification tools.
Free SSL options
Let's Encrypt is completely free, Domain Validated, with 90-day renewal and community support. Cloudflare SSL is free with an account and adds CDN benefits.
SSL best practices
Use TLS 1.2 minimum (ideally 1.3).
Enable Perfect Forward Secrecy and HSTS.
Monitor expiration and automate renewal.
Enable HTTP/2 and OCSP stapling for performance.
Common SSL problems and solutions
Mixed-content warnings: update all resources to HTTPS.
Certificate-chain problems: install the intermediate certificates.
Renewal problems: configure automatic renewal with expiration alerts.
SSL certificate management and the future
Configure expiration notifications, run security scans, monitor performance and keep an inventory with installation documentation. TLS 1.3 improves security and performance, and quantum-resistant cryptography is coming for post-quantum safety.
Conclusion
SSL certificates are essential. Begin with Let's Encrypt, choose hosting with automated installation, and automate renewal so the padlock never lapses.