Electrostatic Memory
Similar to a CRT, electrostatic storage tubes used in the Whirlwind computer in 1950 held a whopping 256 bits each. The bits were "painted" on the surface of the tube, and their electrostatic charges determined their content. See Williams tube. (Image courtesy of The MITRE Corporation Archives.)
Delay Line Memory
In the late 1940s and early 1950s, the memory in the EDSAC and UNIVAC I was made of tubes of liquid mercury that were several feet long. Electrical pulses were converted to sound and back to electrical in a continuous loop. The conversion to sound, which propagates much slower than electricity, slowed down the digital data a fraction of a second and caused the device to function as storage. See EDSAC and UNIVAC I.
Magnetic Drum Memory
This magnetic drum unit was the memory in the IBM 650 computer, introduced in 1954. It held two thousand 10-digit words. That much memory today would fit on the head of a pin, and a very thin pin to be sure. See 650. (Image courtesy of the Hagley Museum and Library.)
Magnetic Core Memory
Two years later, the tubes (above) in the Whirlwind were replaced with magnetic cores, which were far more reliable. The direction of the magnetic energy in the core determined the 0 or 1. Like the tubes, these core planes held 256 bits. See core storage. (Image courtesy of The MITRE Corporation Archives.)
![]() | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2009 The Computer Language Company Inc. All rights reserved. |
Additional Resources
- Remember when FrontPage seemed pretty slick?
- My school teaches...... web design in the conventional way. Intro classes cover HTML, CSS, using JQuery modules or writing basic js. Advances classes teach PHP and such. None of the classes I know of cover CMS.I had a summer internship where I used Drupal. I didn't do any of the...
- Discussion threads 2009-10-29
- Did 'reporters' sink Vista?
- Yes. They made it much worse.There were early driver problems, many devices NEVER got updated for Vista, the fit and finish was and is rough, the extra security was a nag (but should have been DEFENDED and EXPLAINED by the tech pros, instead of being ridiculed), business was right to...
- Discussion threads 2009-10-19
- Alas, Poor Blackberry, I knew him.
- verbsjust my opinion but:I brought (s/b took) it with me when I left the house. ...will be happy to bring (s/b take) me on as a new... just my opinion.Just buy a damn phone.Just buy a normal phone, you know, one that makes and receives calls.You tried phoning people...
- Discussion threads 2009-10-01
- Why you should be glad about Gmail failures
- A future that will never happen."But the way I look at it, every Gmail outage is a small investment I?m willing to make towards a future when I?ll be able to take its reliability utterly for granted."Keep dreaming.They are machines created by humans, maintained by humans, running software created by...
- Discussion threads 2009-09-24
- Happy 30th birthday, Compuserve
- It rocked - in its day...I practically lived on Compuserve in the LATE 70's and early 80's, but to be honest they became pretty irrelevant years ago. In fact, I was surprised to see a headline about them.I still have my compuserve e-mail addressI first started using Compuserve in 1991....
- Discussion threads 2009-09-24
- RIM BlackBerry Storm 2 caught in the wild [video]
- The question is...What is the performance difference between the Storm 2 and the Storm? In its current form and firmware, the Storm is an excellent device. It is responsive and offers a rich user experience in terms of e-mail, web, tethering, and applications.My guess is that Rim decided...
- Discussion threads 2009-08-17
- Microsoft sees sense, kills "three app limit" on Windows 7 Starter edition
- Microsoft sees sense, kills "three app limit" on Windows 7 Starter editionroflThen dont use windows starter edition then! dumbassRE: Microsoft sees sense, kills About the only limitation that doesn't make sense to me is the personalization features... I mean, wtf?I would think that would be an easy hack, but why...
- Discussion threads 2009-05-30
- When Americans were well-trained
- When Americans were well-trainedExpress RailI like the idea! There is nothing express or high speed about traveling by train today in America. In fact from Michigan where i live I can plan on up to 20 hours to the East with long layovers. I see no reason...
- Discussion threads 2009-05-07
- General Motors: It's Time for a Rebranding
- General Motors: It's Time for a RebrandingHave You Been To A Dealer Lately?Look at the Saturn Aura, Chevy Malibu, Pontiac G6 and Saab 9-3. They are all on the same platform Epsilon. Do they all look alike?RE: General Motors: It's Time for a RebrandingI guess you don't realize that the...
- Discussion threads 2009-04-28
- I
- Icloud?So does this mean that I will be able to run my Access 97 databases from the 'cloud', what about all the 100mb photos I have in PSD format, or how about the music files I'm working on on my mac using Logic Express? Where is all the versions of...
- Discussion threads 2009-02-17
- Remembering the '1984' Super Bowl Mac ad
- Remembering the '1984' Super Bowl Mac adThe irony certainly not lost on me[i]But as "1984" turns 25, its images of conformity and totalitarianism have grown increasingly sprinkled with irony.[/i]Apple has become that which they used to fight against. Luckily for them, they have an army of mindless drones apologizing for...
- Discussion threads 2009-01-23
- When Woz speaks who listens?
- Attendees of the Macworld Expo San Francisco next week will get the chance to see Apple co-founder Steve Wozniak on the show floor. A company that makes tablet versions of the MacBook hopes that his appearance in the booth will help sell the product. Good luck to them with this...
- Blog posts 2008-12-31
- Worlds.com patent litigation could ripple through virtual worlds
- Worlds.com patent litigation could ripple through virtual worldsQuake 3 predates this patent by two yearsQuake 3 would seem to run counter to this patent, as would Tribes, and several other online games from the 90s. The core concepts of such online interactions were also presented in the 90s movie...
- Discussion threads 2008-12-30
- The kids like Vista
- While the reviews are mixed from teachers as I finish up the rollout of new Vista-running PCs, the reviews from students are almost universally positive. Maybe it's their fascination with shiny objects (most people will agree that Vista is, at least, pretty), but I think it says a lot...
- Blog posts 2008-09-24
- Office 2.0: an Irregular mashup
- The upcoming Office 2.0 conference is one of the first in the fall calendar that keeps people like me in more airports than I care to think about. It's also one for which I have fond memories. Office 2.0 started out as an idea put out into the Enterprise Irregulars'...
- Blog posts 2008-08-25
- From Chapter one: Data Processing and the IBM Mainframe
- From Chapter one: Data Processing and the IBM MainframeWhen everyone is somebody, then no one's anybody.W.S. Gilbert, Gondoliers.So many managers. An employee without a management title will feel overlooked.Murph, you outline the functional groups for your organization based on the leader. That means the effectiveness of each one...
- Discussion threads 2008-08-15
- Apple chaos theory
- Apple chaos theoryExcuse me !!!"CIOs don't like having technology forced down their throats, particularly not by end users more concerned with being trendy than standardized."Excuse me, since when is this true ? Isn't everyone still banging their heads on the desks because Vista is being shoved down their throats ?...
- Discussion threads 2008-07-21
- Thoughts on Bill Gates
- Thoughts on Bill GatesGood lawyeringOne thing that is often forgotten is the fact that, when Gates purchased and licensed dos to IBM, the contract was the "killer app".It required IBM to pay for DOS on every machine whether they used it or not, while allowing MS to license DOS...
- Discussion threads 2008-06-27
- A place for our stuff
- A place for our stuffI saw him live in '73,It was the nearest I have got to ROFLOL.RE: A place for our stuffIrony is while people were laughing at his jokes, they were really laughing at their own ignorance. I enjoyed George Carlin's no bullsh!t delivery. Tell the truth and...
- Discussion threads 2008-06-23
- Viet-era vets support Iraq war PTSD claims
- After the Vietnam War it took some veterans decades to get their PTSD acknowledged and treated. (Art by Shaun Mullen of Kikoshouse.) Medication, therapy and even religion can all help, but it's a lifetime condition. The memories last a lifetime. Many Vietnam-era veterans are...
- Blog posts 2008-06-06
Neighboring Terms
Premier Vendor Content Whitepapers, webcasts & resources from our Power Center Sponsors
- Keep Up With The Latest In Document Management with The DocuMentor.
-
Doc delivers the scoop on today's enterprise content management, printer maintenance, and all other issues related to document management. It's the DocuMentor Blog.
- Learn more >>
- Learn more about tools to grow your business
-
The Business Essentials Guide provides you useful tools and templates to help grow your business and save you time with automated shipping solutions.
- Save time with the UPS Business Essentials Guide
- Reduce risk. Reduce complexity. Increase reliability.
-
A simplified IT environment isn't just less complex. It's also more reliable. Standardize on a single Linux platform with SUSE Linux Enterprise from Novell, and get the world's most interoperable Linux
- Learn more >>
- Microsoft Dynamics CRM Online - Free Six-Month Trial for Eligible Organizations
-
Microsoft Dynamics CRM Online provides fast online access, simple contact management and better sales performance for a low monthly cost - the best value on the market today.

- Learn more about the free, six-month trial offer>>
Enterprise Applications
- Check out some of the easiest and most powerful ways to boost productivity while saving money on your application infrastructure. See ZDNet's comprehensive Enterprise Application resource center, now!
- New Online Dashboard
- Read about top issues IT decision-makers face every day, plus get cost effective solutions to real life IT problems. Oracle Topline







