Your device sends a request, servers send back data, and your browser displays it

The internet is a network of computers connected by cables and wireless signals. When you open a web browser and type in a web address, your device sends a request through that network to a computer called a server that stores the website. The server sends the website's files back to your device, your browser reads those files, and displays the page on your screen. This happens in seconds, but it involves several steps and many different computers along the way.

You do not need to understand every technical detail to use the internet safely and effectively. But knowing the basic path your information takes — and where it can get stuck or go wrong — helps you troubleshoot problems, understand why something is not working, and recognize when something looks suspicious.

Key Takeaways

  • Your device connects to the internet through an Internet Service Provider (ISP), which is the company that provides your home or mobile internet connection.
  • When you visit a website, your browser sends a request to a server, which sends back the files needed to display the page.
  • Your web address (URL) tells your device which server to contact, and the Domain Name System (DNS) translates that address into a number the internet can understand.
  • Data travels through multiple routers and cables to reach its destination, and the same path is used to send the response back to you.
  • Your Internet Service Provider can see what websites you visit, but encryption (HTTPS) protects the contents of what you send and receive.

How your device connects to the internet in the first place

Your device — whether a computer, phone, or tablet — does not connect directly to the internet. It connects to an Internet Service Provider (ISP), which is the company that provides your internet service. Common ISPs include Comcast, Verizon, AT&T, and local providers. Your ISP owns the cables or wireless towers that carry your data to and from the larger internet.

When you set up internet at home, you either plug an ethernet cable directly into a modem (a device that converts the ISP's signal into data your devices can use), or you connect wirelessly to a router (a device that broadcasts a wireless signal). Your phone or computer then connects to that router, and the router connects to the modem, which connects to your ISP. On mobile devices, your phone connects directly to your mobile carrier's network, which is also an ISP.

Without this connection to an ISP, your device cannot reach the internet at all. If your internet is not working, the problem is usually either with your ISP's service, your modem, your router, or your device's connection to the router — not with the internet itself.

What happens when you type a web address and press Enter

When you type a web address like "www.example.com" into your browser and press Enter, your browser needs to find the server that stores that website. It cannot just search the internet randomly — it needs the exact location. That location is an IP address, which is a unique number assigned to every device and server connected to the internet. IP addresses look like this: 192.0.2.1.

Your browser does not know the IP address of example.com, so it sends a request to a Domain Name System (DNS) server. The DNS server is like a phone book for the internet — it stores the connection between web addresses (like example.com) and IP addresses (like 192.0.2.1). Your ISP usually provides a DNS server, though you can use others. The DNS server looks up the address and sends the IP address back to your browser.

Once your browser has the IP address, it can now send a request to the actual server. This whole process — looking up the address and getting the IP back — usually takes less than a second. If a website is slow to load, the problem is sometimes a slow DNS lookup, though usually it is the server itself or your internet connection.

How data travels from your device to the server and back

Once your browser has the server's IP address, it sends a request across the internet. Your data does not travel in one straight line. Instead, it is broken into small pieces called packets, and each packet is sent separately through the network. Each packet contains a piece of the data, the destination IP address, and the source IP address (your device).

These packets travel through many different routers — computers that direct traffic on the internet — before reaching the destination server. Each router reads the destination address on the packet and sends it toward the next router that is closer to the destination. This is similar to how the postal service works: a letter goes to a local post office, then a regional one, then another, until it reaches the destination address.

When all the packets reach the destination server, the server reassembles them into the complete request, reads what you asked for, and sends the website's files back to your device in the same way — broken into packets, traveling through multiple routers. Your browser receives all the packets, reassembles them, and displays the website on your screen.

Why some websites show a lock icon and others do not

When you visit a website, look at the address bar at the top of your browser. Some websites show a small lock icon next to the address, and the address starts with "https://" instead of "http://". The "s" stands for "secure," and it means the data you send to that website is encrypted — scrambled so that only the website's server can read it.

Without encryption (http), your ISP and anyone else monitoring the network can see what you type into forms, what you search for, and what pages you visit. With encryption (https), they can see that you visited the website, but they cannot see what you did there. This is why you should always look for the lock icon before entering a password, credit card number, or other sensitive information.

Even with https, your ISP still knows which websites you visit — it just cannot see what you do on them. If you want to hide which websites you visit from your ISP, you would need to use a VPN (Virtual Private Network), which is a separate service that encrypts your entire connection.

What can go wrong and why websites sometimes do not load

If a website does not load, the problem is usually one of these: your device is not connected to the internet, your ISP's service is down, the DNS server is not responding, the website's server is down or too busy, or there is a problem with the cables or routers between you and the server.

To figure out which one, try these steps in order. First, check that you are connected to your router — look for the wifi symbol on your device or check that the ethernet cable is plugged in. Second, try visiting a different website. If that works, the problem is with the first website's server, not your connection. If no websites load, restart your router by unplugging it for 30 seconds and plugging it back in. If that does not work, contact your ISP to see if their service is down in your area.

If you can load some websites but not others, the problem might be DNS. Try changing your device's DNS server to a public one like Google's (8.8.8.8) or Cloudflare's (1.1.1.1). Instructions for this vary by device, but searching "change DNS on [your device type]" will show you how. If that fixes the problem, your ISP's DNS server was the issue.

How websites know who you are and remember your preferences

When you visit a website and log in, the server sends your device a small file called a cookie. The cookie contains information that identifies you — not your name, but a unique code. The next time you visit that website, your browser automatically sends the cookie back to the server, and the server recognizes you without asking you to log in again.

Websites also use cookies to remember your preferences, like the language you chose or items in your shopping cart. Some cookies are set by the website itself, and some are set by advertising companies that track which websites you visit. You can see and delete cookies in your browser's settings, and you can set your browser to reject cookies or ask before accepting them.

Cookies are not dangerous by themselves — they are just small text files. But they do allow websites and advertisers to track your activity across the internet. If you want to limit tracking, you can delete cookies regularly, use your browser's "private" or "incognito" mode (which does not save cookies), or use a browser extension that blocks tracking cookies.

Frequently Asked Questions

What is the difference between the internet and the web?

The internet is the network of connected computers and cables. The web is one service that runs on the internet — it is the system of websites, browsers, and servers. Other services on the internet include email, video calls, and online games. You can use the internet without using the web, but you cannot use the web without the internet.

Can someone see my passwords if I use public wifi?

If a website uses https (the lock icon), your password is encrypted and cannot be seen. If a website uses http (no lock), your password can be seen by anyone on the same wifi network. Always check for the lock icon before entering a password on public wifi, and avoid logging into important accounts on unsecured networks.

Why does my internet speed vary throughout the day?

Internet speed depends on how many people are using your ISP's network at the same time. During peak hours (usually evening), more people are online, and speeds slow down. It also depends on how far you are from your router, whether you are using wifi or ethernet, and how many devices are connected to your network.

What is an IP address and why do I need one?

An IP address is a unique number that identifies your device on the internet, similar to a mailing address. Servers need your IP address to send data back to you. Your ISP assigns your device a temporary IP address each time you connect, and that address changes periodically. You do not need to know your IP address for everyday internet use.

Is it safe to click links in emails or text messages?

Links in emails and text messages can be dangerous if they come from unknown senders or look suspicious. Hover over the link (without clicking) to see the actual web address — if it does not match what the link says, do not click it. Legitimate companies rarely ask you to click a link to verify your account or enter sensitive information.