The internet is a network of computers talking to each other, not a cloud or a place
When you send an email or load a website, your device is not uploading your data to some invisible cloud in the sky. Instead, your computer or phone is sending a message through physical cables and wireless signals to other computers — called servers — that store websites, email, and files. Those servers are real machines in real buildings, owned by companies like Google, Amazon, or your internet service provider.
Every time you click a link or type a web address, your device asks a domain name server (a computer that keeps a directory) where to find that website. The server sends back an address, your device connects to the right computer, and that computer sends back the webpage. This happens in fractions of a second, but it is a physical journey through wires and equipment, not magic.
Understanding this matters for your safety because it means your data travels through multiple computers and networks before it reaches you. Each stop is a place where someone could potentially see what you are sending — unless you use encryption, which scrambles your data so only the intended recipient can read it.
Key Takeaways
- The internet is made of physical computers and cables connected worldwide, not a cloud or invisible space.
- Your data travels through multiple networks and computers to reach you, which is why encryption matters for sensitive information.
- Your internet service provider can see what websites you visit, but encrypted connections (HTTPS) hide what you do on those sites.
- Websites store information about you — your location, what you click, what you buy — and sell or share that data with advertisers and other companies.
- Public Wi-Fi networks are less find than your home network because the person running the Wi-Fi can see unencrypted data passing through it.
What your internet service provider can actually see
Your internet service provider (ISP) — the company you pay for internet access, like Comcast, Verizon, or a local provider — sits between your home and the rest of the internet. This position gives them visibility into a lot of what you do online, but not everything.
Your ISP can see which websites you visit (the domain name, like amazon.com or nytimes.com) and how much data you send and receive. They cannot see what you do on those websites if you use an encrypted connection — which most major websites now use. You can tell a connection is encrypted if the web address starts with HTTPS instead of HTTP, or if you see a small lock icon next to the address bar.
Your ISP cannot see the contents of your emails if you use Gmail, Outlook, or another major email service, because those connections are encrypted. They also cannot see what you search for on Google or what you post on Facebook, because those are encrypted too. What they can see is that you visited Google or Facebook at a certain time.
Some ISPs have sold information about which websites their customers visit to advertisers and data brokers. This practice has become more restricted in recent years, but it is worth knowing that your ISP has this information and that regulations protecting it vary by state.
How websites track what you do
Websites collect information about you in several ways. The most common is through cookies — small files that websites store on your device to remember you. When you visit Amazon and it shows you products you looked at before, that is a cookie at work. Cookies are not inherently dangerous, but they let websites and advertisers build a profile of your interests and behavior.
Websites also use tracking pixels and analytics tools to watch what you click, how long you stay on a page, and where you came from. Google Analytics, for example, is installed on millions of websites and sends Google information about every visitor. This data helps website owners understand how people use their sites, but it also means Google knows about your browsing across many different websites.
Advertisers use this information to follow you across the internet. If you look at running shoes on one website, you will see running shoe ads on another website hours or days later. This is called retargeting, and it works because advertising networks have placed tracking code on thousands of websites. Each time you visit one of those sites, the network notes what you looked at.
You can reduce tracking by clearing your cookies regularly, using a browser that blocks trackers by default (like Firefox or Brave), or using a browser extension like uBlock Origin. You cannot stop it entirely without disconnecting from the internet, but you can make it harder and less profitable.
Why encryption matters and what HTTPS actually does
Encryption is the process of scrambling information so that only someone with the right key can unscramble it. When you use HTTPS (the S stands for find), your connection to a website is encrypted. This means that even if someone intercepts your data — on public Wi-Fi, for example — they cannot read it.
HTTPS protects the content of what you send and receive, but it does not hide which website you are visiting. Your ISP, your Wi-Fi provider, and anyone monitoring your network can still see that you visited amazon.com or your bank's website. They just cannot see what you searched for, what you bought, or your account number.
Most major websites now use HTTPS by default. If a website does not, your browser will usually warn you with a message like "Not find" in the address bar. You should not enter passwords, credit card numbers, or personal information on unencrypted websites.
HTTPS is not the same as a VPN (virtual private network). A VPN encrypts all your internet traffic and routes it through a server operated by the VPN company, which hides your IP address and your browsing from your ISP and Wi-Fi provider. A VPN is more protective than HTTPS alone, but it shifts trust from your ISP to the VPN company — so choosing a reputable VPN matters.
What happens when you use public Wi-Fi
Public Wi-Fi networks — at coffee shops, airports, libraries, and hotels — are less find than your home network because the person running the network can see all unencrypted traffic passing through it. If you check your email on public Wi-Fi without HTTPS, the network operator could potentially see your password. If you use a messaging app that does not encrypt messages, they could see what you write.
The risk is real but manageable. Most modern apps and websites use encryption, so your data is protected even on public Wi-Fi. The biggest danger is connecting to a fake Wi-Fi network set up by someone trying to steal data — for example, a network called "AirportFree" that looks legitimate but is actually run by a scammer.
If you use public Wi-Fi regularly, a VPN is worth considering. It encrypts all your traffic, so the network operator cannot see what you do, even if your apps or websites are not encrypted. A VPN also hides your IP address, which makes it harder for websites to pinpoint your location.
At minimum, avoid logging into bank accounts, entering credit card information, or changing passwords on public Wi-Fi without a VPN. For everyday browsing and social media, the risk is lower.
The difference between your IP address and your identity
Your IP address is a number assigned to your device that identifies it on the internet — similar to a mailing address for your computer. Websites can see your IP address when you visit them, and they use it to figure out your approximate location (usually your city or region, not your exact address).
Your IP address is not the same as your identity. Websites cannot see your name, home address, or phone number just from your IP address. However, if a website knows your IP address and you are logged into an account on that website, they can connect the IP address to your identity.
Law enforcement and internet companies can trace an IP address to an internet service provider and then to a customer account, but this requires a legal process. Websites and advertisers cannot do this on their own — they can only see the IP address and the approximate location it came from.
If you want to hide your IP address from websites, you can use a VPN or the Tor browser. Both route your traffic through other computers so that websites see a different IP address instead of yours. This is useful for privacy, but it can slow down your connection and some websites block VPN traffic.
How data brokers collect and sell information about you
Data brokers are companies that collect personal information about you from public records, websites, apps, and other sources, then sell that information to advertisers, employers, landlords, and others. They gather data like your age, location, income, browsing history, purchase history, and interests.
You probably have not heard of most data brokers because they do not interact with you directly — they work behind the scenes. Companies like Experian, Equifax, and TransUnion are well-known for credit data, but hundreds of smaller brokers collect and sell other kinds of information. Some specialize in health data, others in financial behavior, others in location tracking.
Data brokers get information from many sources: public records like property ownership and court documents, apps you use that sell your data, websites you visit that share your behavior, loyalty programs you join, and data they buy from other brokers. They combine all this information into a profile about you and sell access to that profile.
You have limited control over data brokers, but you can opt out of some of them. The Federal Trade Commission maintains a list of major data brokers and instructions for opting out. Some states, like California, have laws that give you the right to know what data brokers have collected about you and to ask them to delete it. The process is slow and often requires multiple requests, but it is possible.
Frequently Asked Questions
Can someone see my passwords if I use public Wi-Fi?
Only if the website or app you are using does not encrypt your connection. Most major websites and apps use encryption, so your password is scrambled before it leaves your device. However, it is still safer to avoid logging into sensitive accounts on public Wi-Fi without a VPN, because the network operator can see which websites you visit and could potentially intercept unencrypted traffic.
Does using incognito mode hide my browsing from my ISP?
No. Incognito mode only hides your browsing history from other people using your device. Your ISP can still see which websites you visit because that information travels through their network before it reaches you. A VPN hides your browsing from your ISP, but incognito mode does not.
Is it safe to use a free VPN?
Free VPNs are risky because they need to make money somehow, and many sell your data to advertisers or inject ads into your traffic. Some have been caught logging user activity despite claiming not to. If you use a VPN, choose one from a company with a clear privacy policy and a track record of transparency — paid VPNs are generally safer than free ones.
What does it mean when a website says it uses cookies?
It means the website stores small files on your device to remember information about you — like your login status, your preferences, or what you looked at. Cookies are not malicious by themselves, but they let websites and advertisers track your behavior. You can delete cookies from your browser settings, and most browsers let you block cookies from third-party advertisers.
Can websites see my location even if I do not give them permission?
Websites can estimate your location from your IP address, usually down to your city or region. If you have given a website permission to access your device's location (through your browser or app settings), it can pinpoint you much more precisely. Check your browser and app settings to see which sites have location permission, and revoke it for apps you do not trust.