SSL and TLS Explained
Web Encryption
When you enter a password or make an online payment you are trusting the website to keep your information safe. SSL and TLS are the technologies that protect your data while it travels across networks. Without them anyone on the path between you and the website could intercept or modify your information.
This article explains what SSL and TLS are, how they work and why they matter.
What SSL and TLS are
SSL stands for Secure Sockets Layer. TLS stands for Transport Layer Security.
SSL was the original security protocol for the web. TLS is the modern upgraded version. Today when people say “SSL” they almost always mean TLS. Browsers no longer support the old SSL versions.
SSL was the foundation. TLS is the evolution.
The goals of TLS
TLS provides three essential protections.
Encryption
Data is scrambled so no one can read it.
Authentication
The browser verifies that you are talking to the real website and not a fake server.
Integrity
The data cannot be changed during transmission. If someone tries to tamper with it the browser detects it.
These three protections create a secure channel.
How TLS works step by step
TLS sounds complicated but it follows a simple structure.
Step 1. Browser connects to the server
The browser says “I want to create a secure connection”.
Step 2. Server sends its certificate
This certificate contains:
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The domain name
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The server’s public key
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The certificate authority signature
Step 3. Browser verifies the certificate
The browser checks:
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Is the certificate from a trusted authority
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Is the certificate expired
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Does the domain match
If any check fails you get a warning.
Step 4. Both sides generate encryption keys
These keys are temporary and unique for every session.
Step 5. Secure communication begins
Now HTTP flows inside the encrypted TLS tunnel.
Your data is safe from snooping, tampering and impersonation.
What is a TLS certificate?
A certificate is like an ID card for a website. It is issued by a trusted third party called a Certificate Authority.
The certificate proves:
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The website owns the domain
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The server controls the private key
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The website is legitimate
Browsers trust only well known authorities.
Types of TLS certificates
Domain Validated (DV)
Basic certificate. Validates only domain ownership.
Organization Validated (OV)
Validates the organization behind the domain.
Extended Validation (EV)
Stronger business verification. Useful for high trust sites.
DV is enough for most websites today.
Why TLS matters
TLS protects:
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Passwords
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Personal data
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Credit card numbers
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Cookies
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API traffic
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Login sessions
Without TLS:
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Anyone on public Wi Fi could intercept your data
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Attackers could redirect you to fake sites
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Session hijacking would be common
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Sensitive data would leak everywhere
TLS is mandatory for modern web applications.
Conclusion
SSL started the web security revolution. TLS continues it with stronger encryption and modern protections. It creates trust between browsers and websites and keeps users safe every time they connect.