What is a web server, and how does it work?
6 min read
Web servers can be said to form the building blocks of the internet. A web server is required to access web applications, web content, and anything accessible via a web browser. Despite how necessary they are to the World Wide Web, understanding how they work — more importantly, how to keep them secure from cyberattacks — is a bit more complex than it may appear. So read on to learn how web servers work.
Table of Contents
Table of Contents
What is a web server?
In the simplest possible terms, a web server is a storage unit or system that hosts content accessed via a web browser. This will be media and text for most web servers, but depending on the website, a web server can also store anything from files to applications.
Aside from storage, web servers are also responsible for retrieving and delivering web content. Web servers can control the speed of how this content is delivered via web acceleration and its overall availability to users. There’s no difference in the type of content users access regardless of the types of browsers a client may use (Chrome, Firefox, Opera). However, there will be slight differences in the display and rendering of the actual image or text depending on the settings of each browser.
How do web servers work?
To understand how a web server works, it’s useful to break it down into its two essential components:
Hardware
Hardware is the physical location of a web server’s content. This can be a dedicated hard drive, a computer, or a similar storage device that can be accessed via the internet. A single web server can host various types of content and even multiple websites through virtual hosting.
Software
A web browser like Chrome or Firefox acts as the primary way to access web content. Web browsers control how a user finds web content online and give them other ways to interact with the web server, such as downloading files or even being redirected to other web servers.
When a user goes on their web browser to interact with a website, the following happens:
The web browser will look for the specific web server hosting the content that the user wants to see. Typically, this web server is identified via a domain name system (DNS) or accessed straight from the web browser’s web cache for less delay in loading the content.
When the web browser finds the correct web server, it sends Hypertext Transfer Protocol (HTTP) requests to its HTTP server. These HTTP requests are processed by the website’s HTTP server, which then looks for the corresponding HTML documents to send to the web browser.
Once the web server finds the corresponding data, it displays the relevant web pages in the web browser or sends the corresponding HTTPS error status code.
This process slightly changes depending on the actual website’s setup or the web browser’s settings. Sometimes, a user will be shuffled along different web servers before finding the specific web pages they’re looking for. However, this is the general process that all web servers and websites follow to allow users access to content, and the two components of a web server — hardware and software — are always necessary for hosting any type of content on the web.
Examples of web server use
Web servers are crucial to hosting and delivering web content to any user looking for it online. A web server can allow users to:
- Download files from a specific server using the File Transfer Protocol (FTP).
- Send and receive emails from other users or web servers.
- Host websites and their web pages, plus additional content like applications.
Web server setups like a home server can help optimize many parts of a user’s online experience. A dedicated web server can host web content and make it available 24/7 to anyone with an internet connection, while multiple web servers can power large domains that contain a lot of information. Some popular web server examples include IIS, Apache Tomcat, Nginx, and Lighttpd.
Dynamic vs. static web servers
Web servers deliver content differently depending on the specific software installed. The many web servers on the internet can be divided into two types:
- Static web server: Has dedicated hardware, such as a computer, and HTTPS software that delivers static web content.
- Dynamic web server: Consists of all of the above, plus an application server and a database that can update dynamic content whenever it is sent to a user.
Static web servers work when displaying simple web content. Common web servers that fall under this category are websites that store content like images, text, or videos. Most static web servers are used for blogs and portfolios, typically content that doesn’t change as the user interacts with it.
On the other hand, dynamic web servers deliver web content that changes depending on user interaction. This type of dynamic content requires more server-side processing but allows more user actions regarding its hosted content. Many of the leading web servers in use online (such as those in social media) utilize dynamic web servers.
Both static and dynamic content will always require web server hardware and a browser for hosting and displaying. The only major difference between the two is that static content is typically delivered to the web browser as is, while dynamic content is usually changed depending on the end user’s actions.
Common types of web servers on the market
Web servers also have dedicated software that helps them run and host content. Web server software can be divided into several types depending on their provider and features:
- Apache web server: Also known as an Apache HTTP server, this server type is an open-source, modular software that works on multiple platforms. It’s one of the most popular web servers used worldwide.
- Linux web server: Arguably one of the most flexible types of web server software, Linux allows for the consistent, high-speed delivery of static and dynamic content to users. An open-source web server, it has extensive customization capabilities.
- NGINX web server: NGINX is another open-source web server that’s more lightweight than other server types and well-suited for delivering static web content. Web browsers that interact with NGINX servers can also benefit from features like email proxy or reverse proxy services.
- IIS web server: Microsoft’s Internet Information Service (IIS) is the web server of choice on any Windows operating system. It’s another popular option for static web servers, FTP servers, or web application servers looking to host PHP scripts.
Ultimately, the best web server configuration will depend on what type of content is hosted on the website. Dynamic content will usually require web server configurations that can handle high volumes of requests, while static content allows a little more leeway with the speed of content retrieval.
Web server security practices
Because of the data web servers contain and how many users pass through them, robust security measures are necessary to ensure no information is compromised. Web servers are usually protected by default with a firewall, although that isn’t the only way administrators and IT personnel can beef up their web server security.
There are other ways to do it, which are described below.
Creating stronger passwords for web server management tools
Passwords are some of the most significant security vulnerabilities in any web server management system. To prevent unauthorized access, passwords must be complex and only given to trusted users and personnel.
Enable HTTPS protocols
The Hypertext Transfer Protocol Secure (HTTPS) can be considered an extension of HTTP. The difference is that HTTPS communications are far more secure and encrypted, allowing for better user confidentiality and increased security for both the web server and the users who try to access its content. SSL and TLS (Secure Sockets Layer and Transport Layer Security, respectively) protocols can also be applied for more protection.
Update web server software
Since web server software controls most of how a website (and, by extension, the owner or owners of that website) interacts with its users, ensuring that the software is updated can be a reliable way to protect any information on the website. This is particularly important for websites that process plenty of user traffic and store data like financial information.
Secure web servers for more secure websites
Understanding how web servers work is the first step to protecting a website and its users. Generally, web servers can be protected with basic measures and mindfulness about safe security practices. However, being proactive about web server security and implementing security practices like VPN servers will always be in everyone’s best interests. Investing in web server security solutions should always be a priority for web pages that contain sensitive data or websites that process a lot of personal information.