How Web Servers Function: An Overview

Type a web address, hit enter, and a page appears on your screen in less than a second. Nothing about that feels complicated from where you’re sitting, but behind that one click is a fast, layered handoff between browsers, domain name systems, and specialised software that most shoppers, students, and even many business owners never think about. For anyone studying e-commerce, understanding this handoff is not optional trivia. Every online store, from a small Instagram-linked shop to a large marketplace, depends entirely on a web server doing its job correctly, quickly, and securely. This post breaks down exactly what happens when a user requests a website, and introduces the two software systems, Apache and IIS, that power a huge share of the web.

What is a web server, exactly? 🔗

The term “web server” actually refers to two connected things. There is the hardware: a physical or virtual machine that stores website files (HTML, images, videos, application code) and stays connected to the internet. And there is the software: a program running on that machine whose job is to understand incoming requests and respond with the right content. When people in e-commerce talk about “the server,” they usually mean the software layer, since that is what actually decides how a request gets handled.

This entire setup follows what is known as the client-server model. The “client” is the user’s browser or app, and the “server” is the remote system hosting the website’s resources. The client asks; the server answers. Every product page you browse, every cart you fill, and every checkout you complete on an e-commerce site runs on this same basic exchange, repeated thousands of times over.

Step 1: The user requests a website 🔗

The process begins the moment someone types a URL into a browser or taps a link. The browser reads the domain name in that URL, say, an online store’s website address, and prepares to find out where that domain actually “lives” on the internet. But domain names are only for humans. Computers route traffic using numerical IP addresses, not words. So before anything else can happen, that domain name needs to be translated.

Step 2: DNS translates the domain into an IP address 🔗

This translation step is handled by the Domain Name System, or DNS, which functions like the internet’s phonebook, matching human-friendly domain names to the machine-readable IP addresses that point to actual servers. Without DNS, users would need to memorise long strings of numbers instead of simple website names.

How the lookup actually happens 🔗

When a domain name has not been looked up recently, the request is sent to a recursive DNS resolver, usually operated by the user’s internet service provider or a third-party DNS service. This resolver does the legwork of tracking down the correct IP address on the browser’s behalf. According to GeeksforGeeks’ explanation of DNS, this system operates in a hierarchical, distributed manner, moving from root servers to top-level domain servers (which handle endings like .com or .in) and finally to the authoritative server that holds the actual DNS records for that specific domain. That authoritative server returns the correct IP address, which then gets passed back to the browser.

To keep this process fast, resolvers cache results for a set period, known as the Time-To-Live (TTL) value. This is why a site usually loads faster the second time you visit it. Even with all these hops, DNS resolution for a cached or nearby lookup typically finishes in well under a second, which is why the entire step feels invisible to users.

Step 3: The browser connects to the web server 🔗

Once the browser has the IP address, it opens a connection directly to the server hosting the website. This connection uses the Transmission Control Protocol (TCP), typically over port 80 for regular HTTP traffic or port 443 for secure HTTPS traffic. For any e-commerce website handling payment details or personal information, this HTTPS connection is essential, since it encrypts data moving between the browser and server.

Step 4: The server processes the request and responds 🔗

With the connection established, the browser sends an HTTP request asking for a specific resource, such as a homepage, a product listing, or an image file. The web server software receives this request, figures out what is being asked for, retrieves or generates the relevant content, and sends it back as an HTTP response.

For a simple page, the server might just fetch a stored HTML file. For a dynamic e-commerce page, like a personalised recommendations section or a live stock count, the server often needs to query a database, run some backend code, and assemble the page on the fly before sending it. Once the browser receives this response, it renders the page, images load, styles apply, and the buttons become clickable.

Why this process matters for e-commerce 🔗

This entire sequence, DNS lookup, connection, request, response, happens in a fraction of a second on a well-configured site. But delays anywhere in this chain directly affect revenue. Slow DNS resolution, a server struggling under heavy traffic, or a poorly optimised response time can all push page load speeds past the point where shoppers stay engaged. Retail platforms in India increasingly deal with traffic spikes during sale events, festive seasons, and flash discounts, which makes reliable, fast-responding web servers a genuine business requirement, not just a technical detail. A server that goes down during a high-traffic sale does not just lose that one visitor; it loses every visitor arriving at that moment.

Apache and IIS: the software running the show 🔗

Web server software is what actually interprets requests and manages responses on the server side. Two of the most established names in this space are Apache and Microsoft IIS (Internet Information Services), and understanding their differences is useful groundwork for anyone studying e-commerce infrastructure.

Apache HTTP server 🔗

Apache is free, open-source software maintained by the Apache Software Foundation. It is known for running across multiple operating systems and for a modular design that lets administrators add features, such as security modules, URL rewriting, or caching, only when needed. Because the source code is public, it can be inspected, customised, and patched by a large community of contributors, which has kept it a common choice for businesses that want flexibility and control over configuration.

Microsoft IIS 🔗

IIS is Microsoft’s proprietary web server, built specifically to run on Windows Server. According to Microsoft’s own documentation comparing IIS and Apache, both are among the most widely used web servers globally, though they take different technical approaches under the hood. IIS integrates tightly with other Microsoft products, including ASP.NET applications and SQL Server databases, and offers a graphical interface for configuration, which many administrators find more approachable than editing text-based configuration files.

Independent comparisons echo this split in strengths. Comparitech’s review of IIS and Apache notes that IIS is built on widely used, publicly documented protocols like HTTP, SMTP, and FTP, and receives regular security patches directly from Microsoft, while Apache’s open-source nature gives site owners more room to inspect and adjust its behaviour themselves.

Where the market stands today 🔗

Neither Apache nor IIS dominates the web the way Apache once did in its early years. Newer software such as Nginx has grown rapidly, and recent tracking by industry usage statistics based on W3Techs data shows Nginx now ahead of Apache in overall market share, with Apache’s installed base concentrated in long-running deployments and shared hosting environments. IIS, meanwhile, remains the standard choice specifically for organisations already committed to the Windows and .NET ecosystem. For a commerce student, the takeaway is less about picking a “winner” and more about recognising that the right web server depends on the technology stack, budget, and operating system a business has already chosen.

Putting it all together 🔗

From a single click to a fully rendered page, a web request travels through DNS resolution, a network connection, and server-side processing, all coordinated by software like Apache or IIS working quietly in the background. For e-commerce specifically, this is not abstract computer science. It is the invisible infrastructure that determines whether a customer’s shopping experience feels instant and trustworthy, or slow and frustrating enough to abandon the cart altogether.

What do you think? If you were setting up an online store today, would the cost savings of open-source Apache outweigh the tighter Windows integration that IIS offers? And how much do you think page-loading speed actually influences whether a shopper completes a purchase?

References

1. https://www.cloudflare.com/learning/dns/what-is-dns/
2. https://www.ibm.com/think/topics/dns-server
3. https://www.geeksforgeeks.org/computer-networks/domain-name-system-dns-in-application-layer/
4. https://learn.microsoft.com/en-us/iis/web-hosting/migrate-to-the-microsoft-web-platform/iis-for-apache-administrators
5. https://www.comparitech.com/net-admin/iis-vs-apache/
6. https://rafftechnologies.com/learn/guides/nginx-vs-apache-which-web-server-2026