Timeline of Computer History

<h2 class="title">Commercial Networks Multiply</h2>

CompuServe's Network Control center

Commercial Networks Multiply

The mid-1970s brings a number of commercial networks for corporate customers and professionals to choose from. Most are packet-switched, like Telenet, Tymnet, and other major players. The ill-fated Datran and a couple of others are circuit switched like a telephone system. Six year old CompuServe is also becoming a major supplier of corporate network services; it’s consumer-oriented CompuServe Information Service will follow at the end of the 1970s.

<h2 class="title">Community Memory</h2>

Community Memory terminal, Leopold’s Records, Berkeley

Community Memory

Anyone can walk up and use this terminal, connected to a timeshared mainframe computer, for posting messages and announcements. That's a radical idea when computers are mostly inaccessible to ordinary people, and seen by the counterculture as tools of government and corporate power.

<h2 class="title">DEC RL01</h2>

DEC RL01 User’s Guide


The DEC RL01 is introduced as a successor to DEC's RK05 drives. It was an attempt to lower maintenance costs while bolstering disk drive reliability. It was initially released with a 5 MB capacity, and two years later a 10 MB version was put on the market. Also, head alignment tools were removed, as maintenance on these parts was costly and time-consuming. Future disk drives largely adopted this feature.

<h2 class="title">MITS Altair 8800 kit appears in <em>Popular Electronics</em></h2>

Altair 8800

MITS Altair 8800 kit appears in Popular Electronics

For its January issue, hobbyist magazine Popular Electronics runs a cover story of a new computer kit – the Altair 8800. Within weeks of its appearance, customers inundated its maker, MITS, with orders. Bill Gates and Paul Allen licensed their BASIC programming language interpreter to MITS as the main language for the Altair. MITS co-founder Ed Roberts invented the Altair 8800 — which sold for $297, or $395 with a case — and coined the term “personal computer”. The machine came with 256 bytes of memory (expandable to 64 KB) and an open 100-line bus structure that evolved into the “S-100” standard widely used in hobbyist and personal computers of this era. In 1977, MITS was sold to Pertec, which continued producing Altairs in 1978.

<h2 class="title">MOS 6502 is introduced</h2>

MOS 6502 ad from IEEE Computer, Sept. 1975

MOS 6502 is introduced

Chuck Peddle leads a small team of former Motorola employees to build a low-cost microprocessor. The MOS 6502 was introduced at a conference in San Francisco at a cost of $25, far less than comparable processors from Intel and Motorola, leading some attendees to believe that the company was perpetrating a hoax. The chip quickly became popular with designers of early personal computers like the Apple II and Commodore PET, as well as game consoles like the Nintendo Entertainment System. The 6502 and its progeny are still used today, usually in embedded applications.

<h2 class="title">Southwest Technical Products introduces the SWTPC 6800</h2>

Southwest Technical Products 6800

Southwest Technical Products introduces the SWTPC 6800

Southwest Technical Products is founded by Daniel Meyer as DEMCO in the 1960s to provide a source for kit versions of projects published in electronics hobbyist magazines. SWTPC introduces many computer kits based on the Motorola 6800, and later, the 6809. Of the dozens of different SWTP kits available, the 6800 proved the most popular.

<h2 class="title">Tandem Computers releases the Tandem-16</h2>

Dual-processor Tandem 16 system

Tandem Computers releases the Tandem-16

Tailored for online transaction processing, the Tandem-16 is one of the first commercial fault-tolerant computers. The banking industry rushed to adopt the machine, built to run during repair or expansion. The Tandem-16 eventually led to the “Non-Stop” series of systems, which were used for early ATMs and to monitor stock trades.

<h2 class="title">VDM prototype built</h2>

The Video Display Module (VDM)

VDM prototype built

The Video Display Module (VDM) marks the first implementation of a memory-mapped alphanumeric video display for personal computers. Introduced at the Altair Convention in Albuquerque in March 1976, the visual display module enabled the use of personal computers for interactive games.