Hard Disk Geometry Physical Sizes Also called Form

Hard Disk Geometry

Physical Sizes (Also called Form Factor) • Hard Drives currently come in 2 main sizes: 2. 5” and 3. 5” • 2. 5” Drives are for laptop computers. • 3. 5” drives are for desktop computers. • Both sizes can be placed into cases and used as external drives that connect to the computer with a USB cable.

What is a hard drive for?

Back to Binary – 0 s & 1 s, off & on, + & - , positive & negative • Every document, every picture, every game, every website, every computer program is made up of one or more files. • Every file is a block of arbitrary information, or resource for storing information. • Information is described using groups of words, symbols, and numbers. • Words are made of letters. or symbols. and, along with numbers are made of characters. J ɶ 3 % c * ) 43 ╠ ~ abc ¥ ͽξ • Every character is made of bytes. • Every byte is made up of bits • A bit is either a 0 or a 1, on or off, + or -, positive or negative. • A hard disk drive is a magnetic storage device. It records with positive and negative charges, thus recording information.

Hard Disk – Internal Geometry • The disk spins at RPMs. Current drives operate at 5, 400 RPM, 7, 200 RPM, 10, 000 PRM and 15, 000 RPM. • Data is magnetized on the disk at either positive or negative charges (just like binary) • Disks are first divided into concentric circles called Tracks • Tracks are then divided into blocks called Sectors • Sectors typically hold 512 bytes of data