The first personal computer was the Altair 8800, released in January 1975
The Altair 8800 arrived in January 1975 as a kit you had to assemble yourself. It cost $395 (or $1,995 fully assembled), had no keyboard or monitor, and displayed output as blinking lights on the front panel. Despite these limitations, it is widely recognized as the first computer marketed to individual users rather than businesses or institutions.
The Altair was built around the Intel 8080 processor and came with 256 bytes of memory—roughly enough to store a single paragraph of text. You programmed it by flipping switches on the front, and the results appeared as patterns of lights. The computer arrived in Popular Electronics magazine as a cover story, and the response was when ready: thousands of people ordered kits, even though most had no clear idea what they would do with one.
What made the Altair significant was not its power but its price and availability. Before 1975, computers were room-sized machines that cost tens of thousands of dollars and belonged to universities, corporations, and government agencies. The Altair proved that a functional computer could be small and cheap enough for a hobbyist to own.
Key Takeaways
- The Altair 8800, released in January 1975, is recognized as the first personal computer sold to the general public.
- It cost $395 as a kit or $1,995 fully assembled and required users to program it by flipping switches on the front panel.
- The Altair had 256 bytes of memory and used the Intel 8080 processor, making it far less powerful than computers today but revolutionary for its time.
- The computer's appearance in Popular Electronics magazine sparked widespread interest and proved that affordable computers could reach individual users.
- Other early personal computers followed within a few years, including the Apple II (1977) and the Commodore PET (1977).
Why the Altair 8800 mattered more than its specs suggest
The Altair's real importance lay in what it represented: proof that computers did not have to be locked behind corporate or academic doors. Before the Altair, if you wanted to own a computer, you had to be a large organization with a large budget. After the Altair, hobbyists and small businesses could buy one.
The kit format was intentional. MITS, the company that made it, knew that many buyers wanted to understand how computers worked from the ground up. Assembling the Altair yourself meant learning its architecture. This hands-on approach attracted engineers, programmers, and curious tinkerers who would later start their own computer companies.
Two young programmers named Bill Gates and Paul Allen saw the Altair in that Popular Electronics issue and wrote a version of the BASIC programming language for it. That software became the foundation of Microsoft. Steve Wozniak and Steve Jobs, inspired by the Altair's existence, began designing the Apple I in a garage. The Altair did not create the personal computer industry by itself, but it opened the door and showed that the door could be opened.
The Apple II and Commodore PET arrived two years later
While the Altair proved the concept worked, it remained a machine for hobbyists. The next wave of personal computers brought machines that ordinary people could actually use without a degree in electronics.
The Apple II launched in April 1977 and came fully assembled with a keyboard, color graphics, and a cassette drive for storage. It cost $1,298, which was expensive but not out of reach for small businesses and serious hobbyists. The Apple II had a cleaner design, better software support, and a more intuitive interface than the Altair. It became the first personal computer to sell in large numbers—tens of thousands of units in its first few years.
The Commodore PET also arrived in 1977, priced at $595 to $795. It was more affordable than the Apple II and came with everything built into one unit: keyboard, monitor, and storage. The PET found its way into schools and small offices, making it one of the most widely used computers of the late 1970s.
What "personal computer" actually meant in 1975
The term "personal computer" did not mean what it means today. In 1975, it meant a computer small enough and cheap enough for one person to own, not a computer designed for everyday consumer use. The Altair required you to understand binary code, flip switches in the right sequence, and read output from blinking lights.
By the early 1980s, the definition shifted. Personal computers came with screens, keyboards, and software you could actually run without programming knowledge. The IBM PC (1981) and the Commodore 64 (1982) brought computing to offices and homes in ways the Altair never could. But the Altair came first, and it proved the market existed.
The role of the Intel 8080 processor
The Altair's power came from the Intel 8080, a processor released in 1974. The 8080 was not the first microprocessor—the Intel 4004 came out in 1971—but it was the first one powerful enough and affordable enough to serve as the brain of a personal computer.
The 8080 ran at 2 megahertz and could perform about 200,000 operations per second. For comparison, a modern smartphone processor runs at speeds measured in gigahertz and performs billions of operations per second. But in 1975, the 8080 was a marvel. It made the Altair possible, and later versions of the same processor family powered the IBM PC and early versions of the Commodore 64.
How the Altair led to the home computer boom
The Altair's success created a market. Manufacturers saw that people would buy computers, and they began designing machines aimed at different audiences: hobbyists, small business owners, schools, and eventually home users.
Between 1975 and 1985, the personal computer industry exploded. The Apple II became the standard in schools and creative industries. The IBM PC became the standard in offices. The Commodore 64 became the best-selling computer of all time, reaching millions of homes. None of this would have happened without the Altair proving that the market existed and that people wanted computers in their lives.
The Altair itself faded quickly. By 1980, it was obsolete. But the companies and people it inspired—Microsoft, Apple, and countless others—shaped the computing world for decades to come.
Frequently Asked Questions
Was the Altair 8800 really the first personal computer?
It depends on how you define "personal computer." The Altair 8800 was the first computer marketed and sold to individual users as a consumer product. Earlier computers existed, but they were sold only to institutions. Some people point to earlier hobbyist computers or kits, but the Altair was the first to reach a mass audience and spark a commercial market.
Could you actually do anything useful with an Altair 8800?
Not much by today's standards. With 256 bytes of memory, you could write very short programs. Most Altair owners used it to learn how computers worked or to experiment with programming. Some wrote straightforward games or mathematical programs. The real value was educational and experimental, not practical.
How much would an Altair 8800 cost in today's money?
The $395 kit price in 1975 would be roughly $2,000 to $2,500 in today's dollars, depending on which inflation measure you use. The fully assembled $1,995 version would be around $10,000 to $12,000 today. That made it expensive but not impossibly so for a serious hobbyist or small business.
Did Bill Gates and Steve Jobs both work on the Altair?
Bill Gates and Paul Allen wrote software for the Altair—specifically, a version of BASIC that let people program it more easily. Steve Jobs and Steve Wozniak were inspired by the Altair's existence but built the Apple I as a separate machine. Jobs and Wozniak were not directly involved with the Altair itself.
What happened to MITS, the company that made the Altair?
MITS was acquired by Pertec Computer Corporation in 1977, just two years after the Altair's release. The Altair line was discontinued as newer, more powerful computers entered the market. The company that created the first personal computer did not survive the industry it helped create.