I have a son who has a photographic memory. Its enviable to say the least. He can recall things from a long time past in great detail. He can learn song lyrics at a dizzying pace. I haven't been given the same talent and so have to use mnemonics and other tricks to remember things.
Computers have "memory" too, they have a perfect memory (barring a failure as discussed in the blog about backups). There is really more than one type of "memory" for a computer. Int this blog I am going to talk about the memory that stays even when your computer is off.
Most of your PCs information is stored on a hard disk drive abbreviated HDD. A mechanical device that stores information magnetically on platters that resemble very shiny metal CDs. The drive actually magnetizes small portions of these disk platters when it stores information on them. Think of it as a big platter with thousands of little compass needles. When "reading" the disk, the drive detects those same magnetic spots and interprets them as information. The big benefit to this is that the magnetized spots stay magnetized when you turn your computer off. The data stays for the same reason a magnetic compass doesn't need batteries to operate. Your pictures, word processor files, videos, spreadsheets and other documents reside on millions of tiny compass needles on a metal platter somewhere inside your computer.
This is different from RAM a type of volatile memory that disappears when you turn your computer off, but that is a discussion for another day. So how much do you need? When choosing a hard disk drive size there are several factors to take into consideration. First, what is you budget? Hard drive pricing seems to follow a predictable curve. There is a premium to pay to get a drive of any size. Then is seems you can add 50%-100% capacity and not pay nearly that much for it. For example it may cost you $100 for an 80 GB hard disk drive, but only $110 for a 120 GB hard disk drive and only $150 for a 200 Gb hard disk drive. However this panacea of cheap capacity will find its zenith and the price will shoot up again as you find the upper limit of current hard disk capacity. my opinion is buy in that "sweet spot" just before the pricing shoots up. That way you will get the most out of your dollar.
