Application System/400

Definition of Application System/400

The Application System/400 (AS/400) is a family of mid-range computer systems, also known as IBM iSeries, designed by IBM and introduced in 1988. It is widely popular for its stability, reliability, and flexibility in running multiple applications simultaneously. The system supports various programming languages and database management systems and is widely used by businesses for financial, personnel, and inventory management applications.


The phonetic pronunciation of “Application System/400” is: æplɪˈkeɪʃən ˈsɪstəm/ˈfɔrˈhʌndrəd

Key Takeaways

  1. Application System/400 (AS/400) is an integrated system designed by IBM featuring extensive hardware and software compatibility, making it a powerful and scalable platform for businesses.
  2. AS/400 is well-known for its robust security features, such as object-based security and auditing capabilities, ensuring the safety and reliability of data and applications.
  3. The system supports multiple programming languages and relational database management, allowing flexibility and adaptability for a variety of business applications and industries.

Importance of Application System/400

The Application System/400, often abbreviated as AS/400, is a crucial term in technology as it represents a mid-range computer system introduced by IBM in 1988.

This system gained importance as a comprehensive, highly integrated and user-friendly platform, widely used for enterprise resource planning (ERP) and multiple mission-critical applications.

The AS/400’s highly adaptable architecture, compatibility with various hardware and software systems, and built-in support for e-commerce and web services made it a popular choice for businesses across the globe.

Over the years, it has evolved into the IBM iSeries and then into IBM Power Systems, exemplifying its continued relevance in improving business efficiency, data management, and system performance.


The Application System/400, commonly known as AS/400, is a proprietary mid-range computer system developed by IBM in 1988, intended to serve the needs of small and medium-sized businesses. The primary purpose of the AS/400 was to provide businesses with a scalable, reliable, and secure computing platform for running various mission-critical applications, such as Enterprise Resource Planning (ERP), payroll processing, sales, and inventory management systems.

Its user-friendly interface, robust architecture, and powerful technologies made it an ideal choice for companies looking to integrate multiple applications and streamline their overall business operations. Over the years, the AS/400 has evolved into the IBM iSeries platform, which continues to ensure the seamless integration, high availability, and reliability that the original AS/400 was renowned for.

This advanced business platform encompasses hardware, software, and operating system components that facilitate the development, deployment, and management of e-business applications. Drawing on the strengths of its predecessor, the IBM iSeries also provides additional capabilities such as support for open standards, web and mobile applications, as well as integration with other platforms.

As a result, the AS/400 legacy continues to empower organizations around the world with the technology needed to maintain efficient and effective business processes.

Examples of Application System/400

The Application System/400 (AS/400), now known as IBM iSeries, is a highly integrated and reliable IBM server platform that supports a wide range of business applications. Here are three real-world examples of organizations using AS/400 technology:

Manufacturing: A mid-sized manufacturing company uses AS/400 to manage its entire production process, from planning and scheduling to inventory management. The AS/400 enables efficient and accurate production tracking, improving the company’s ability to quickly respond to customer demands and provide a high level of customer service. In this scenario, the system is used to manage the company’s Enterprise Resource Planning (ERP) software, which helps streamline production and operational processes.

Healthcare: A large hospital network uses AS/400 as the backbone of its electronic health record (EHR) system to securely store and manage patient medical data. The system not only provides a centralized location for accessing and updating patient records but also ensures the security and confidentiality of sensitive patient information. By utilizing the AS/400, the hospital can efficiently manage patient data and ensure proper billing, diagnoses, and treatment options for patients.

Banking & Finance: A regional bank relies on AS/400 to manage its core banking operations, including customer transactions, account management, loan processing, and reporting. AS/400 supports the bank’s services through a range of banking applications and offers robust security measures, allowing the bank to meet regulatory requirements while also providing efficient and seamless financial services to its customers.These examples demonstrate the flexibility and reliability of AS/400 technology in addressing various industry-specific needs.

Application System/400 FAQ

What is the Application System/400?

The Application System/400, also known as AS/400 or IBM iSeries, is a family of mid-range business computing systems built by IBM. It is designed to provide a robust and scalable platform for running various business applications and services.

What are the key features of the AS/400?

Some key features of the AS/400 include its integrated DB2/400 database, native support for multiple programming languages like RPG, COBOL, CL, and Java, a built-in security system, and support for various data storage and backup options.

Why is the AS/400 still relevant today?

Although released in 1988, the AS/400 remains relevant because of its reliability, scalability, and security. IBM continues to support and update the platform, now known as IBM i, making it a viable choice for businesses requiring a stable and proven system to run crucial applications.

What are the primary programming languages used on the AS/400?

The primary programming languages used on the AS/400 include RPG (Report Program Generator), CL (Control Language), COBOL, and Java. Additionally, developers can use other languages such as C++, PHP, Python, and Node.js through open-source support on the platform.

How does the AS/400 handle file and database management?

The AS/400 handles file and database management through its integrated DB2/400 database, also known as IBM i DB2. It supports a wide range of data types and indexing methods, and provides a high level of integration with various programming languages and tools on the platform.

What are the hardware components of the AS/400?

The AS/400 hardware components typically include a processor, memory, storage devices, communication cards, and expansion slots. The specific configuration depends on the model and requirements of the system being used.

Related Technology Terms

  • Midrange computer
  • IBM iSeries
  • OS/400 operating system
  • Integrated database management
  • Business application programming

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