If you know "quite a bit about them" then there is no need for you to ask.

the most basic answer to you question is the RAM

everythin you see on screen, including the operating system, has to be loaded into the ram.

the thing about RAM (random access memory) is that when it looses power, all information is lost.. gone for ever. Thats why you have to shut down a computer with an advanced operating system on it. That way it saves settings and files to the hard drive before the power is cut.

Once power is cut and then turned back on. All of the critical OS systems have to be "loaded" back into the system memory.

They are, however, working with new memory types that equal the speed of modern RAM that do not loose their information one powered down. So i see in the future, that after the OS is loaded, all you will have to do is flip a switch and everything will be just as you left it.

But for now you will have to deal with boot up times. You CAN however cut these times significally by using the windows feature "hibernation" but your computer in hibernation and what that does is (as simply as can be explained here) takes a snap shot of the ram.. saves it to the harddrive. then the next time you power on your computer, windows simply loads that snap shot back into the ram and you have your computer as you left it when you powered down. If you have a slow computer this will significally reduce load up times. I use it for my laptop at work.

although it is a good idea to do a cold boot every once in a while.

indeed i agree, Vista has a new version of suspend that is trully amazing, (and works!) the PC can be powered off (dont unplug it!) and powered in in about half the time of a hibernate, i timed my system to be useable after 10 seconds of hitting the power button!

It is resetting system defaults and memory allocation.

lol

Well we could go into computer basics and that would last for about 4 weeks. Followed by computer languages (4 weeks), followed by microprocessor architecture (4 weeks)...

Its not a light bulb. Its a sophisticated device that makes millions of calculations per second. Opening up that porn site takes processing time.

Wouldn't that be nice.....

i think some day it may be possiable

But what i think hes really asking is why can't computers run on just enough electricity to retain the memory in the RAM so you wouldn't have to reboot everytime, Like a PDA.

well, there is a type of memory/drive that can do that, I dont recall the name. the current problem with it however..is that as soon as you loose power to the computer you loose everything stored.
maybe someone else can expound on what I'm sure I am describing incorrectly.

+ if you used a trs80 or a vic20, or any number of the tape loaded computers or even the big ole floppy drives, you would be thankful; for the speed we currently have.

I, for one..cant wait to see how fast they are 10 years from now.

NAND, is the memory you are talking about, it is stupidly slow compared to system ram, it wouldnt serve to replace ram at the moment, however, with vista and new up an coming hard drives you can use a feature called ready drive, the drive has x MBs of NAND ram built in to it that acts like a buffer, for small files this would decreasing the time of loading system files and for random searches.

For larger files it would make no difference as its speed is to slow.

ya that can be done. Actually the hard disk does retain the data, even after PC is switched off.
but the whole point of using RAM, is its speed. RAM is a different kind of memory, created in order to provide great speeds for efficient computing.

You can stop the nonimportant applications from loading by going to START > RUN > in the Run box, type, msconfig

then click OK > go to the Startup tab.

The same reason you don't walk into a light pole because it's there .You must walk around it .

if you want everything to load without your permission just check all the boxes in msconfig. but this will slow everything down. you want the options to start things yourself. hope that helps.

its because you set up your on type of things you whant.

well its because the magnet inside of the computer needs to start up before loading things.

i think he means the magent in the servo controling the hard disk head, that is indeed the slowest part of the computer and partially why the computer is slow to start.

ok.. if i were to xplian to u in full details .. then it ll take days.
in very brief i can tell you that computer has 2 types of memory - primary memory (hard disk) and secondary memory (RAM - Random access memory).
While you are running the computer, everything that you do, needs lots of support iinfo, which is stored on RAM.

But the capacity of RAM is limited. also it is a temporary memory,that is the contents of RAM are deleted once you switch off the computer.
So what do you do ? Actually this is where the hard disk comes handly. Everything is saved on it. Next time when you boot up, all the things are reloaded on RAM.

keep in mind that here the info refers to various Softwares that help your PC to run, icluding the OS, drivers etc. While running the PC, you do directly use the info on hard drive also.

its wise not to talk about hard disks being memory, greatly confuses some people!