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monsieurdozier
March 20th, 2008, 06:36 PM
I have a problem with alot of people not knowing the difference between their RAM and their hard drive. They tend to believe that if they were to buy an external hard drive, it would fix their RAM problems, mainly a lack there of.

So I was wondering, do any of you know any good simple analogies I can use to explain the difference between RAM and Hard Drive space?

Monsieur Dozier

The Titan
March 20th, 2008, 06:50 PM
Hard drive : Trunk
ram : glove box

in the sense that you are constantly putting and taking things from the glove box but the trunk is more of a permanent home. IDK, just a shot.. Thought this was kind of fun. You can tell them getting a bigger trunk in your car isn't gonna make the glove box any bigger

LaRoza
March 20th, 2008, 06:52 PM
I have a problem with alot of people not knowing the difference between their RAM and their hard drive. They tend to believe that if they were to buy an external hard drive, it would fix their RAM problems, mainly a lack there of.

So I was wondering, do any of you know any good simple analogies I can use to explain the difference between RAM and Hard Drive space?

Monsieur Dozier

A hard drive is a card holder (playing hards), RAM is what you have in your hand.

intense.ego
March 20th, 2008, 06:53 PM
Hard drive: backpack
RAM: pocket

The backpack can store more, but stuff in the pocket is more accessible and quicker to access as well.

The Titan
March 20th, 2008, 06:54 PM
you guys are way better than me at this :(

Het Irv
March 20th, 2008, 07:00 PM
I like the glove box one, put instead of saying that the person uses it more, say that it is more convenient. If you want to get real techie, you can say that the back seats that fold down to give you access to the trunk is like pagefiles.

popch
March 20th, 2008, 07:24 PM
Cash in purse vs. account in bank.

Pethegreat
March 20th, 2008, 07:44 PM
Ram: Door to door mailman
Hard Drive: 53ft trailer full of mail.

chucky chuckaluck
March 20th, 2008, 07:47 PM
adding more dry firewood isn't going to solve your wet matches problem.

az
March 20th, 2008, 08:02 PM
Ram is the size of your desk work space. Disk space is the number of file folders you have in your office.

The smaller your desk size, the more time you waste putting files and papers away and getting others out. If you have a lot of ram, you can work on a lot of different documents at the same time.

If you have a lot of file folders in your office, you can work on a lot of stuff without having to leave your office.

Ram is for work, not storage.

LaRoza
March 20th, 2008, 08:07 PM
@OP For simplicty, do not mention hard drive cache, swap/paging, and L2 + L1 cache until they get the basic concept that hard drives are just for storing information, and RAM is used to run and use it.

aaaantoine
March 20th, 2008, 08:52 PM
I always try to explain how it works directly, and what signs you need to observe to decide whether you need to upgrade hardware. That lesson usually goes as follows:

If you don't have enough RAM, your computer will begin to use the hard disk for temporary storage. Because the hard disk is slower than RAM, everything slows down. If software performance is slow, and your computer's disk light indicates that it is working hard (both conditions must be met), it could be a sign that you need more RAM. (I would then go on to explain how to read the numbers in the Windows Task Manager.)

If your computer simply tells you "There is not enough free disk space", this is an indication that you should either clear out some of the old junk or buy a bigger hard disk. This has nothing to do with RAM. (I would then show the person how to see how much disk space is available.)

As for an analogy, I relate the two to human memory.

- RAM is like short term memory; the stuff you are using right this second.
- A hard disk is like long-term memory; the stuff that you want to remember later.
- Your short term memory is quick, because it is what you are working with currently or recently. When you are done with your short term memory, you either forget about it entirely or store some of it in your long term memory.
- Your long term memory holds a lot of information, but recalling this information can take some time.

This analogy doesn't do a very good job of explaining memory swapping, however.

SomeGuyDude
March 20th, 2008, 09:03 PM
If a hard drive is your brain, RAM is notecards.

Think about studying for a test. You know all the material, but recalling it all on short notice is the hard part. So you have a notecard. You write down all the important stuff. Now, if you have a small notecard, you can't write down very much, so you have a tough time with the test because you still need to pull out so much from your head.

Get another notecard, and you can whip through the test faster because you've got more information on instant recall.

Erunno
March 20th, 2008, 09:14 PM
RAM is like a brain. It needs power continuously and if it shuts down (i.e. the Grim Reaper harvests you) it loses all its data irrevocably.

A hard-drive is like a book. It keeps its contents a long time even without a power supply and its data can be loaded into volatile memory (i.e. your gray matter) and data can dumped into it for future reference.

drascus
March 20th, 2008, 09:38 PM
Hard drive space is equivalent to all the stuff you own. Ram is equivlent to the stuff you can use and hold in your hand right now. So having more hands would allow you to do more things. having a bigger house would only allow you to have more things not necessarily use them.

alzie
March 20th, 2008, 09:47 PM
I was thinking more like a book versus a bookshelf.

herbster
March 20th, 2008, 10:44 PM
RAM is like a box of chocolates...

mike.oldfield
March 20th, 2008, 10:54 PM
Ram is the size of your desk work space. Disk space is the number of file folders you have in your office.

The smaller your desk size, the more time you waste putting files and papers away and getting others out. If you have a lot of ram, you can work on a lot of different documents at the same time.

If you have a lot of file folders in your office, you can work on a lot of stuff without having to leave your office.

Ram is for work, not storage.

I've always seen that as one of the best ways to describe it. That's the way my Cisco tutor taught it to me, and it makes so much sense.

DublinPCservices
March 20th, 2008, 11:01 PM
The only analogy that is gets close to being correct is this one
Cash in purse vs. account in bank.


that is...
small amount of storage instantly available vs. a large amount of storage available after a delay

RAM is used because accessing data on the hard drive is slow, in comparison to accessing RAM, a hard drive hit takes an *eternity*.

That's why RAM exists.

tyggna1
March 20th, 2008, 11:03 PM
Here's one I used when I worked for Dell tech support:

Whenever your computer processes something, imagine that it's baking a cake.

When you're done putting the flour into the mixer, you'd like to put it right next to the mixer. In your computer, this is called the registers. They're fast, quick, and easy to use.

Once the registers fill up, which they always do, the next closest spot is the kitchen table. This is L1 cache, and it's on the processor. It's much bigger than the registers, but still pretty quick.

When the table fills up, you'd go out to the coffee table in the living room. That's L2 cache. The next closest spot for storage is your ram. This is like going around to the back side of your house, opening up your cellar, and putting it on a shelf. Kinda inconvenient, especially when you need to get another cup of flour--but still reasonable for space.

Lastly, because sometimes your cellar fills up, the next available spot for storage is about a 4-5 hour drive away (in my case, I say boise Idaho). So, every time you need a cup of flour off your hard drive, you have to hop in your car, drive for four hours to your storage unit, pick up the bag, and drive back for another four hours.

While that's kinda a long analogy, it really helps to show comparative speeds and distances inside the computer, and it's pretty accurate for SATA hard drives running at anywhere from 7.2k rpm to 10k rpm. (if it's solid state, change the driving time to about an half-hour or so).

monsieurdozier
March 21st, 2008, 08:05 PM
The only analogy that is gets close to being correct is this one
Cash in purse vs. account in bank.


that is...
small amount of storage instantly available vs. a large amount of storage available after a delay

RAM is used because accessing data on the hard drive is slow, in comparison to accessing RAM, a hard drive hit takes an *eternity*.

That's why RAM exists.

I think that is my favorite analogy as well.

Thanks everyone for good responses. This should make my life a little easier.

Monsieur Dozier

popch
March 21st, 2008, 08:12 PM
I think that is my favorite analogy as well.

Unless, of course, people are beginning to ask when the interest is due.

L473ncy
March 21st, 2008, 09:09 PM
RAM is like L1 Cache

Hard Drive is like Tertiary storage

(This is going on an extreme and I don't think anyone without knowledge of computers will know what this means)

What I mean is
(ie RAM = Faster access/smaller space whereas Hard Drive = slower but more storage)

aaaantoine
March 21st, 2008, 10:04 PM
Reviewing the thread, my favorite is az's analogy.

RAM : HDD :: Desk : Filing Cabinet

It best represents the sort of work that gets done in these spaces. With a computer, you can either load data from the HDD (take files out of the cabinet) or create something new. With this in mind...

RAM : HDD :: Wallet : Bank

This breaks down because money is not akin to information (unless you play The Matrix Online).

popch
March 21st, 2008, 11:08 PM
RAM : HDD :: Wallet : Bank

This breaks down because money is not akin to information (unless you play The Matrix Online).

In that case, I suggest to go to your bank and to ask to see the money you deposited. Your money in the bank is nothing but information. That turns out to be a fortunate coincidence when your bank happens to burn down.

beercz
March 21st, 2008, 11:25 PM
I describe the difference thus:

RAM is like the kitchen sink. Hard disk is like a resevoir.

When you need to use the sink you fill the sink with water which comes from a resevoir and when you have finished with the sink you empty the water which returns to the resevoir.

Data is loaded into RAM (sink) from the hard disk (resevoir) when needed. When the data is finished with (and saved) it is removed from RAM and put back on the hard disk.

hth