The Microsoft founder remembers the origins of a digital revolution
By Technology Correspondent | 4 April 2025
As Bill Gates approaches his 70th birthday, he has taken a moment to reflect on a piece of computer code he wrote 50 years ago—a piece of work that would eventually change the course of technology forever.
Although primitive by today’s standards, the programme Gates wrote on a teletype machine was a catalyst for personal computing and laid the foundation for the multitrillion-dollar technology empire that Microsoft would become.
This week, as Microsoft prepares to celebrate its golden anniversary, Gates reminisced about those early days in a blog post, calling it “the coolest code I’ve ever written”.
How it all began: A simple idea that changed the world
It was the January 1975 issue of Popular Electronics that sparked Gates’ inspiration. The magazine featured a groundbreaking article about the Altair 8800, a new type of minicomputer that could be powered by a tiny microprocessor from Intel, an obscure company at the time.
For Gates, then a freshman at Harvard University, and his childhood friend Paul Allen, this article was a eureka moment. The two friends immediately saw an opportunity—they could create software to control this new machine.
There was only one problem: they hadn’t actually written the code yet.
Undeterred, the pair contacted Ed Roberts, CEO of Micro Instrumentation and Telemetry Systems (MITS), the company behind the Altair 8800. Gates and Allen boldly claimed they had already developed the necessary software.
This bluff set off a frantic two-month coding marathon, during which Gates and Allen worked with little sleep, developing a version of BASIC—a programming language originally created at Dartmouth College in 1964—to run on the Altair computer.
Without even having a physical Altair computer to test it on, they wrote and debugged the programme in a virtual simulation. Against all odds, when Allen flew to MITS headquarters to test their software on an actual Altair machine, it worked perfectly.
The birth of Microsoft and the software revolution
This early success paved the way for Microsoft, which Gates and Allen officially founded in April 1975.
The code they had written became the first operating system for the Altair, marking the dawn of the personal computing era. Over the next decades, Microsoft would go on to dominate the software industry, creating Windows, Word, Excel, and PowerPoint, among other innovations.
“That was the revolution,” Gates reflected in a video accompanying his blog post.
“That was the thing that ushered in personal computing.”
The significance of their early work cannot be overstated. Before Microsoft, computers were massive, expensive machines, used primarily by businesses and research institutions. Gates and Allen helped bring computing to the masses, setting the stage for the digital world we live in today.
A year of reflection for Bill Gates
As he nears 70, Gates has been on something of a nostalgic journey.
- In February, he released a memoir about his early years, including his experiences as a socially awkward but gifted child.
- He also recently marked the 25th anniversary of the Bill & Melinda Gates Foundation, which he founded after stepping down as Microsoft’s CEO in 2000.
- He has reflected on his often tumultuous relationship with Steve Jobs, the late Apple co-founder, whose company will celebrate its own 50th anniversary next year.
More Read
Looking back, Gates still seems amazed at how far his vision has come.
“Fifty years is a long time,” Gates remarked. “It’s crazy that the dream came true.”
Microsoft’s legacy and the future of technology
While Gates left his day-to-day role at Microsoft years ago, the company he co-founded remains a global technology powerhouse.
Under CEO Satya Nadella, Microsoft has embraced cloud computing, artificial intelligence, and quantum computing, reaching a staggering market valuation of $2.8 trillion.
And while the original Altair 8800 is now a relic of the past, its legacy lives on in every personal computer, smartphone, and AI-powered system we use today.
For Gates, that simple teletype programme from 50 years ago wasn’t just code—it was the beginning of a technological revolution.
