Microsoft Releases Open Source Version of Bill Gates’ 1978 BASIC for Free Use by Developers This title emphasizes the open-source aspect of the release and highlights the historical significance of the BASIC language created by Bill Gates, aiming to attr

September 4, 2025

Redmond, Washington – Microsoft made a notable move Wednesday, releasing the complete source code for Microsoft BASIC for 6502 Version 1.1, the programming language that fueled the initial boom of personal computers in the late 1970s. this release unlocks a piece of technological history, offering unprecedented access to the code that powered iconic machines like the commodore PET, VIC-20, Commodore 64, and Apple II.

A Legacy in 6,955 Lines of Code

The released code, totaling 6,955 lines of assembly language, is now available on GitHub under a permissive MIT license. this allows developers, historians, and enthusiasts to freely use, modify, and distribute this foundational software. Microsoft Co-founder Bill Gates himself commented on the release, recalling his role in creating the 6502 BASIC alongside Rick Weiland, and a curious feature he added: the “WAIT” command.

for a generation, Microsoft’s BASIC served as the gateway to programming. Users, ofen for the first time, could interact with computers by typing simple commands like “10 PRINT ‘HELLO'” and “20 GOTO 10”, experiencing the direct control a computer offered. The interpreter translated these instructions, line by line, into machine code the processor could understand. The impact extended beyond simple text on screen, inspiring an entire generation of programmers and innovators.

The Commodore PET, introduced in January 1977, relied on the MOS 6502 processor and a version of Microsoft BASIC to operate.

Engineering Marvel in a Resource-Constrained Era

The ingenuity of Microsoft’s BASIC is particularly striking when considered within the technological constraints of the time. The 6,955 lines of code were meticulously crafted to deliver maximum functionality within extremely limited memory capacity. In the late 1970s, Random Access Memory (RAM) could cost hundreds of dollars per kilobyte – a stark contrast to today’s prices.

The MOS 6502 processor, the engine behind this BASIC interpreter, played a vital role in making computing accessible. Its low cost-approximately $25,compared to the $200 charged by competitors-allowed manufacturers to build affordable computers. The 6502 powered not only early personal computers but also gaming consoles like the Atari 2600 and the Nintendo Entertainment System.

The Licensing Deal commodore Shouldn’t Have Missed

In 1977, Commodore struck a deal with microsoft, licensing the 6502 BASIC for a one-time fee of $25,000. This agreement granted Commodore perpetual rights to ship the software without any ongoing royalties. While a considerable sum at the time, the long-term implications were significant. Commodore’s widespread sales of computers equipped with Microsoft BASIC could have generated tens of millions of dollars in revenue for Microsoft had a per-unit licensing model been negotiated.

The released version, 1.1, includes refinements jointly implemented by Commodore engineer John Feagans and Bill Gates in 1978. These improvements, including enhancements to memory management-known as “garbage collection”-resulted in “BASIC V2” on the Commodore PET.

The Enduring Influence of BASIC

While largely superseded by more advanced programming languages, BASIC’s legacy extends far beyond its historical role. It remains a valuable tool for teaching introductory programming concepts due to its simple syntax and ease of use. Several modern programming languages, like Visual Basic .NET, trace their lineage back to the original BASIC interpreter.

Did You Know? BASIC was initially an acronym for Beginner’s All-purpose Symbolic Instruction Code, reflecting its intended audience and purpose.

Feature	BASIC (1978)	Modern Programming Languages (e.g., Python)
Memory Usage	Extremely Low (Kilobytes)	Typically much Higher (megabytes/Gigabytes)
Syntax	Simple, Line-Based	More Complex, Block-Based
Primary Use	Early Personal Computing, Education	Wide Range of Applications (Web, Data Science, AI)

Frequently Asked Questions about Microsoft BASIC

• What is Microsoft BASIC? Microsoft BASIC is an early programming language interpreter that was instrumental in popularizing personal computing in the late 1970s and early 1980s.
• Why is the source code release significant? The release allows for historical study and potential adaptation of foundational computer code, contributing to our understanding of computing’s origins.
• What computers used Microsoft BASIC? popular machines included the Commodore PET, VIC-20, Commodore 64, and apple II.
• What is the MIT license? The MIT license is a permissive open-source license allowing anyone to use, modify, and distribute the code, even for commercial purposes.
• How much did Commodore pay for the BASIC license? Commodore paid a flat fee of $25,000 for a perpetual license without royalties.

What are your earliest memories of using BASIC? Do you think open-sourcing historical code like this is a beneficial practice for the tech community?

How dose the open-sourcing of 1978 BASIC contribute to the preservation of computing history?

Microsoft Releases Open Source Version of Bill Gates’ 1978 BASIC for Free Use by developers

In a surprising move that bridges computing history with modern development practices, Microsoft has released an open-source version of the 1978 BASIC interpreter originally created by Bill Gates and Paul Allen. This release isn’t just a nostalgic trip; it’s a valuable resource for developers, retro-computing enthusiasts, and anyone interested in the roots of modern programming languages. The code is available on GitHub, marking a significant moment for the preservation and accessibility of computing history.

Understanding the Historical Meaning of 1978 BASIC

BASIC (Beginner’s All-purpose Symbolic Instruction Code) was revolutionary in it’s time. Designed to be easy to learn, it democratized programming, bringing it to a wider audience than ever before.

Early Microcomputers: The 1978 BASIC was specifically tailored for the Altair 8800, one of the first commercially accomplished personal computers.

Bill Gates’ Origins: This version of BASIC was a pivotal project for a young Bill Gates and Paul Allen, effectively launching Microsoft.

Influence on Modern Languages: BASIC’s influence can be seen in numerous subsequent programming languages, including Visual Basic and even aspects of modern scripting languages.

What’s Included in the open-Source Release?

The release encompasses more than just the core interpreter. Microsoft has provided a extensive package, including:

The Original 1978 BASIC Source Code: The complete source code for the interpreter, allowing developers to examine and modify the original implementation.

Documentation: Original documentation from 1978, offering insights into the design and functionality of the language.

Examples: Sample programs demonstrating the capabilities of the 1978 BASIC interpreter.

Build Instructions: Guidance on how to compile and run the interpreter on modern systems.

This comprehensive approach ensures the release is genuinely useful for both historical study and practical experimentation.

Why Open Source Now? Microsoft’s Rationale

Microsoft’s decision to open-source this historical artifact is multi-faceted.

Preservation of Computing History: Open-sourcing ensures the code remains accessible and preserved for future generations.

Educational Value: The release provides a unique learning possibility for students and developers interested in the evolution of programming languages.

Community Engagement: Encouraging community contributions and modifications can lead to new insights and improvements.

Retrocomputing Revival: The growing retrocomputing community will find this release invaluable for restoring and experimenting with vintage hardware and software.

Benefits for Developers: Beyond Nostalgia

While the historical aspect is compelling, the open-source BASIC release offers tangible benefits for modern developers.

Learning from the Past: Studying the design of a simple interpreter can provide valuable insights into compiler construction and language design.

Embedded Systems: The compact nature of BASIC makes it potentially suitable for resource-constrained embedded systems.

Educational Projects: The code can serve as a foundation for educational projects teaching essential programming concepts.

Reverse Engineering: Developers interested in reverse engineering can analyze the code to understand how early interpreters worked.

Practical Tips for Working with the 1978 BASIC Code

Getting started with the open-source BASIC code requires a bit of readiness.

1. GitHub Repository: Clone the repository from https://github.com/microsoft/basic.
2. Build Environment: Follow the build instructions provided in the repository to compile the interpreter for your operating system. Expect to use a C compiler.
3. Emulation: consider using an emulator (like MAME) to run the BASIC interpreter in a simulated Altair 8800 environment for an authentic experience.
4. documentation Review: Familiarize yourself with the original documentation to understand the language’s syntax and features.
5. Community forums: Engage with the online community (reddit, dedicated forums) to share your experiences and learn from others.

Real-World Applications & Case Studies (Potential)

While direct commercial applications are limited,the release has already sparked several engaging projects:

Retro Gaming: Developers are using the BASIC interpreter to recreate classic text-based games.

Historical Research: Researchers are analyzing the code to gain a deeper understanding of the early days of personal computing.

Educational Tools: Instructors are incorporating the BASIC interpreter into their curriculum to teach fundamental programming concepts.

Microsoft 365 and the Future of Development

While seemingly disconnected, Microsoft’s commitment to both historical preservation and modern development