What is Apache? In-depth overview of Apache web server

The Apache HTTP Server, commonly known as Apache is a free and open-source web server, that delivers web content through the internet. As open-source software, its original source code is freely available for developers to view and collaborate. This has made Apache a favorite among developers who create and configure Apache models to expand its functionality and improve on its core features.

Developed and maintained by the Apache Software Foundation, it quickly became one of the most widely used web servers due to reliability, flexibility, and extensive module support. Since its infancy in 1995, Apache has been a core technology that helped spur the initial growth of the internet.

Before exploring the ins and outs of Apache, you have to understand what a web application is and the standard architecture that supports it. Let’s start there.

The current web server landscape

The internet is powered by various web server software, each with its own strengths and use cases. While Apache has long been one of the most popular web servers, the landscape is constantly evolving with new technology.

In the late 1990s and early 2000s, Apache dominated the market, serving over 50% of the internet's active websites. During this time, Microsoft's IIS (Internet Information Services) was also an option but not nearly as popular.

Fast forward to 2025, and while Apache still serves a large portion of websites, its market share has shrunk from 50% to 26.9%. Meanwhile, NGINX, a relatively new player to the landscape, is taking the lead, running on 33.8% of websites. Microsoft IIS now accounts for just 4.1% of the market. As web technologies advance, new web applications and server software continue to shape the industry.

Apache web application architecture

Apache is a key component in the web application stack, but it doesn’t work alone. One of the most common web application stacks is LAMP, which stands for:

• Linux: The operating system that handles the operations of the application.

• Apache: The web server software that processes requests and serves web assets and content via HTTP.

• MySQL: The database server that stores all your information in an easily queried format.

• PHP: The programming language that works with Apache to help create dynamic websites and applications.

While exact adoption numbers vary, the LAMP stack has remained a favorite in the industry because it’s flexible, reliable, and completely free. Thanks to its ease of use, many web applications are built on some variation of this stack.

How web applications are structured

No matter their purpose, most web applications have similar architecture and structure. Here are some of the key components that work together to keep things running efficiently:

• Firewalls: Your first line of defense against cyber threats. Depending on how the firewalls are configured, they protect the web application from external threats and internal vulnerabilities.

• Load balancers: Distributes traffic across the web servers.

• Web servers: This is where Apache comes in. It handles HTTP(S) requests and application servers.

• Database servers: Manages asset storage and backups.

Depending on your infrastructure, your database and application can live on the same server although it’s recommended that they stay separate. When these components work in sync, you get a fast and secure web application that can handle anything.

How does Apache Web Server Work?

Apache functions as a way to communicate over networks from client to server using the TCP/IP protocol. Apache can be used for various protocols, but the most common is Hyper Text Transfer Protocol/Secure, or HTTP/S, which is one of the main protocols on the web, and the one protocol Apache is most known for.

HTTP/S defines how messages are formatted and transmitted between web browsers and web servers, instructing them on how to handle requests and commands. The difference between HTTP and HTTP/S lies in security:

• HTTP (port 80) - Unsecured communication between the client and server.

• HTTP/S (port 443) - Encrypted communication using SSL/TLS for added security.

The Apache HTTP server project allows you to configure its behavior through Apache configuration files. By default, Apache listens to the IP addresses configured in its configuration files that are being requested. This is one of the many strengths of Apache.

With the Listen directive, Apache can accept and route specific traffic to certain ports and domains based on specific address-port combination requests. By default, Listen runs on port 80, but Apache can be configured to handle multiple domains and ports, allowing for virtual hosting on a single server. For example, you can have domain1.com listening on port 80, domain2.com on port 8080 and domain3.com on port 443 using HTTPS all on Apache.

Once a message reaches its destination or recipient, Apache sends a notice to the original sender that their data has successfully arrived. If there’s an error in receiving data or some packets were lost in transit, the destination host or client sends a Not Acknowledged, or NAK message, to inform the sender that the data needs to be retransmitted.

With its ability to route traffic and support secure communication, Apache HTTP server remains one of the most popular web servers in the world, and is commonly used by majority of companies.

Why Apache remains a standout web server

One of Apache's strengths is its ability to handle high traffic loads with minimal configuration. It’s highly scalable, and due to its modular functionality, you can customize Apache configuration to meet your specific needs. You can also remove unnecessary Apache modules to make it more lightweight and efficient.

Apache is also great for developers, as they have the freedom to add various modules such as SSL, server-side programming support (PHP), and load balancing to enhance how Apache operates.

Another benefit of Apache is its ability to run on multiple operating systems including Linux, MacOS, and Windows. If you know how to configure Apache on Linux, you can also do it on another system. The main differences comes down to directory path and installion processes.

Features of Apache web server

Apache web server offers several features that make it a great choice for web hosting and and server management. Some of its standout features are:

• Handling of static files

• Loadable dynamic modules

• Automatic indexing

• .htaccess

• IPv6 compatability

• Supports HTTP/2 support

• FTP connections

• Gzip compression and decompression

• Bandwidth throttling

• Supports Perl, PHP, Lua script languagess

• Load balancing

• Session tracking

• URL rewriting

• Geolocation based on IP address

Alternatives for Apache HTTP Server

While Apache web servers are very popular, they’re not the only web servers on the market. Below are several of alternatives for Apache HTTP servers:

• Nginx

• Apache Tomcat

• Lighttpd

• Cherokee

• Microsoft IIS

• Appweb

• Hiawatha

While Apache HTTP server is a web server designed to serve static web pages, Apache Tomcat is an application server built to serve Java applications. Web pages can still be served through Apache Tomcat, but it will be less efficient than using an Apache HTTP server.

Start monitoring your Apache web servers today

Throughout the last few decades, Apache has proven to be a staple in many popular stacks and the backbone of the early internet. While its popularity is declining and the options of web server choices are increasing, Apache still plays a pivotal role in many technology stacks and companies' system infrastructure. Even with new technologies and servers coming out nonstop, Apache is still a technology every developer should learn how to handle and configure.

Managing Apache logs is crucial for maintaining performance and security. By integrating Apache with Sumo Logic, you can gain insights into Apache logs, detect anomalies and optimize your server’s performance.

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