Web Server vs. Application Server: What’s the Difference?

Servers handle the requests your browser makes while you’re online. Two types of servers technically handle these requests: the web server and the application server.

This article compares web server vs. application server to help you understand when to use one or the other. 

Distinguishing between the two can sometimes be tricky. Web servers nowadays use scripting languages like hypertext preprocessor (PHP) or active server page (ASP) to make content dynamic. While this is happening, application servers have started using HTTP to communicate and offer reverse proxy, load balancing, and various other services to improve performance and reliability. It helps developers focus more on app development than on infrastructure. 

Due to these overlaps, professionals refer to both servers as web application servers. Many use the two terms interchangeably since they can easily perform both jobs. 

Some companies that rely on web servers use web server acceleration tools to reduce response time, speeding up content delivery. This helps when there are numerous requests to respond to. Application servers generally take longer to respond since they deal with complex business logic.

What are the key differences between a web server and an application server?

Here are some key differences between web vs. application servers that you can take away. Let’s compare the two.

• Functionality and content type: Web servers handle HTTP requests to deliver static content to the client. On the contrary, application servers deliver dynamic content based on business logic. 

• Processing: Web servers don’t process any business logic. This allows them to respond faster compared to application servers. The latter may require more processing power and time since they manage complex user requests. 

• Middleware services: Middleware acts as a framework between applications' front-end and back-end. Application servers offer connection pooling, messaging services, transaction management, and other middleware services. Web servers don’t provide these. 

• Load balancing: This application serves as built-in support for load clustering and balancing. It can be easily scaled to manage loads efficiently. On the other hand, web servers require additional tools to balance load and failover. 

How does a web server work?

A web server manages all the bits and pieces of a website's code and data. Whenever you type a website's URL into your browser, you’re really looking for the web server where that website lives.

Websites with static content like articles or images work with web servers. However, modern web pages include several interactive elements, such as filling out a form. These interactions need an application server to work smoothly. We detail the way application servers operate in a few sections, but first, let’s discuss use cases for web servers.

What are web servers used for?

Web servers extensively manage websites and data. They handle browser requests in order to send correct responses, ensure communication with legitimate users, and keep malicious hackers out of the picture. 

During heavy traffic inflow, web servers control the data that travels back and forth to prevent slowdowns or website crashes. This helps web servers manage more visitors easily. Some organizations use web server accelerator software to reduce response time, while they also employ compression techniques to improve connection speed. 

With server-side web scripting, developers can make pages that adapt based on how users interact. Programming languages like PHP, Python, and Ruby make it possible, helping developers add more interaction and personalization. 

These servers often use virtual hosting to run multiple websites or applications. This makes for efficient resource usage and keeps costs down. 

What are common examples of web servers?

Below are some common examples of web servers you might find engineers talking about.

Nginx

Nginx serves web content and handles reverse proxying to direct web traffic to multiple sources. It employs load balancing for distributing traffic across multiple servers, making the server fast and efficient. 

The server can also handle email proxying and provide HTTP caching. Nginx uses HTTP caching to store standard responses to requests. When a similar request comes up, Nginx uses the old responses to reply. 

Several companies like Dropbox, Zynga, and Netflix use Nginx to manage heavy incoming traffic. 

Apache HTTP Server

Apache HTTP Server, usually called Apache, emerged in 1995 and became well-known for its reliability and flexibility. It powered the majority of the websites for a long time. Until the end of 2019, Apache ran over 24% of all websites and around 31% of the busiest sites. 

The server’s longevity and continuous use prove its robust features and capabilities can manage major traffic volume. 

How does an application server work?

Now that we’ve covered web servers let’s get into the nitty-gritty of application servers.

Application servers make web servers interact better with dynamic content. They use application logic and connect the web server with different sources. They also facilitate application code communication with other systems and databases to bring a better web experience to users.

For example, when you shop online, you’re interacting with the application server as you add items to your cart or update your delivery details. 

What are application servers used for?

Application servers make it easier to communicate with databases and other systems. They fulfill complex requests from your browser, facilitating mobile or computer functionality. Application servers do the heavy lifting to get the content users want. 

Application servers store cache data so that retrieving the same content in the future is hassle-free. to They also ensure the data flows smoothly, and the request and response channel is secure enough to keep information safe.

There are different types of application servers. Some major in handling several user requests simultaneously, while others focus on improving applications. Below are three common types of application servers you’ll probably come across.

• Active servers run scripts on the server side and communicate with databases to generate dynamic content. They’re good at managing data while providing you with real-time updates.

• Web information servers are application servers that specialize in finding the web content you need. They go through digital archives to find the pages you need. These servers focus on delivering pages that change based on your interactions. 

• Component servers host and manage small software pieces known as components. You can build various features with them while updating applications. This lets you improve existing applications more easily. 

What are common examples of application servers?

Here are some common examples of application servers. They play a significant role in delivering dynamic content straight to Java applications. 

Apache Tomcat

Apache Tomcat caters to Java applications. It runs small Java programs on a server called Java Servlets to answer web requests and create web pages with JavaServer Page code (JSP) while supporting Java Enterprise Edition applications. 

After its release in 1998, Apache Tomcat became a preferred choice for Java web applications due to its holistic support for Java technologies and open-source nature. 

Glassfish

Glassfish came around in 2006 and supported Java applications, Servlets, and standards. Sun Microsystems added dual capabilities that meant that Glassfish could act like an application and web server to deliver static content while running complex Java applications. 

Developers loved this added flexibility for working in Java environments. 

Web server vs. application server: FAQs

Got more questions? We have the answers.

Q1. Can a web server act as an application server?

Web servers can handle basic dynamic tasks using scripts, but they don’t replace full application servers that manage complex logic, transactions, and integrations.

Q2. Do all websites need an application server?

No. Websites that serve mostly static content can rely on a web server alone. Applications with user accounts, forms, or real-time updates typically need an application server.

Q3. What is a web application server?

A web application server combines web server capabilities with application logic, allowing it to serve content while processing backend operations.

Q4. Which is more secure: a web server or an application server?

Both play a role in security. Web servers handle traffic filtering and request routing, while application servers enforce business rules, authenticate users, and control data access.

Q5. Is Nginx a web server or an application server?

Nginx is primarily a web server and reverse proxy. It’s commonly paired with an application server to handle dynamic workloads.

The verdict

The differences between web server vs. application server make it clear that they have different purposes. Web servers are better when you want faster content delivery. However, application servers work better when you need to support complex application logic and deliver dynamic content. 

Learn more about application servers and how to choose the right one for your business.

This article was originally published in 2024. It has been updated with new information.