On this day in economic and business history...

International Business Machines (NYSE:IBM) unveiled the world's first hard-disk-drive-equipped computer on Sept. 13, 1958. IBM's 305 RAMAC had a 3.75-megabyte internal hard disk drive with 50 magnetic disks that could spin at 1,200 revolutions per minute, and it was able to retrieve data in about 600 milliseconds. The computer was so large that it had to be moved by forklift.

The 305 RAMAC was rented to businesses in need of real-time accounting for a monthly fee of $3,200, which would amount to approximately $310,000 per year in current dollars. IBM built more than 1,000 of these systems between 1958 and 1961. However, the RAMACs were never essential to IBM's business: In 1962, all 1,000 RAMACs rented year-round would have generated only about 1.5% of the company's total revenue.

The internal hard disk IBM pioneered would become one of the two core technologies of the PC revolution once manufacturers figured out how to shrink them down to a more reasonable size. Today, Seagate (NASDAQ:STX) and Western Digital (NASDAQ:WDC) have effectively conquered the entire industry, but competition between the two continues to drive progress forward. Just take a look at how advanced Seagate's modern hard disk drive is when compared to the RAMAC's drive:

Specification

IBM 350 

Seagate Barracuda 

Improvement

Physical size

60 in. x 68 in. x 29 in.

1 in. x 4 in. x 5.8 in.

See below

Total displacement

821.67 cubic feet

23.2 cubic inches

99.98% decrease

Drive space

3.75 megabytes

3 terabytes

83,885,980% increase

Disk speed

1,200 rpm

7,200 rpm

500% increase

Data seek time

600 milliseconds

9 milliseconds

98.5% decrease

Cost (1 year)*

$310,000

$125 

99.96% decrease

Source: IBM and Seagate press releases. *Adjusted for inflation.

Seagate shipped its 2 billionth HDD in 2013, just four years after reaching the 1 billion-unit milestone. The entire HDD industry now ships nearly 600 million units per year, with a total annual storage capacity estimated at roughly 300,000 petabytes. A petabyte is roughly a billion megabytes, so in cumulative terms, the HDD industry now produces about 300 trillion times the capacity of one RAMAC HDD every year. That's enough space to store about 150 billion high-definition movies -- or about ten complete sets of Peter Jackson's Tolkien films.

Harold and Kumar's favorite restaurant
The first White Castle opened on Sept. 13, 1921 in Wichita, Kan. It was the first modern "fast food" restaurant in America, and true to its name, this original establishment very much resembled a white castle. Its founders had to strike out in a world still accustomed to rather slow food, although automats had helped develop the fast-food concept with meals delivered by vending machines in New York and other cities earlier in the century. To that end, they developed new methods for quickly and efficiently cooking hamburgers. The venture was greatly aided by the participation of J. Walter Anderson  who had invented both the hamburger bun and the modern grill five years earlier.

This quick and appetizing new venture became an immediate hit, and similar restaurants soon began to pop up across the country. Two decades later, the first McDonald's (NYSE:MCD) opened in California, but it was not until 1955 that the fast-food kingpin began to take off, several years after its founders had restructured the company to resemble White Castle. Today, McDonald's is the world's largest fast-food company, but it's only one part of an enormous industry that now boasts more than 50,000 restaurants in the United States (some estimates go as high as 200,000 restaurants) and more than 500,000 restaurants in total around the world.

Fool contributor Alex Planes owns shares of Seagate Technology. Add him on Google+ or follow him on Twitter @TMFBiggles for more insight into markets, history, and technology.

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