Application server definition
An application server is a special kind of server that holds and runs applications. Its job is to split data processing tasks between itself and its users, usually over a network. This kind of server lets users interact with or use the server-side logic of web applications through different ways, often including HTTP.
Application servers sit in the middle of a common three-tier architecture, acting as a link between the user-facing front end and the database. This middle layer, where the application server is, manages the business logic, which is basically the set of rules that controls how data and the user interface interact.
In short, the application server works like a bridge. It handles and carries out user requests, fetches data from databases, runs the business logic, and gives back the results. Application servers help software applications run smoothly by handling user requests and delivering results.
See also: application delivery controller, application management
Examples of application servers
- Java application servers, like Apache Tomcat and IBM WebSphere, are designed to run web applications written in the Java programming language. They support the entire suite of Java EE technologies, making them ideal for enterprise-scale applications.
- Microsoft .NET application servers are specifically tailored for applications written in .NET languages, like C# or VB.NET. They're integrated with the Windows operating system.
- PHP application servers, like Zend Server, cater to applications written in PHP, so they come with an environment to develop, deploy, and manage PHP applications.
- Python application servers, like Gunicorn, serve applications written in Python. They provide a Pythonic and easy-to-configure environment for deploying Python web applications.