Sector – Fan Area of Disc [MiniTool Wiki]
Sector and Hard Drive
The most basic component of the hard disk is disc ( coated with magnetic medium ), which is made of hard metal material. The number of disc on hard disks with different capacity is different. Every disc has two sides to record information. Disc is divided into many sector areas. Each area is called a sector, which is the smallest storage unit on hard disk. Generally speaking, every sector can store 512 bytes of information. Some hard disk manufactures and software developers are planning to develop new standard - every sector stores 4096 bytes information.
A physical block on hard disk has to be located by using three parameters: cylinder number, sector number and head number. Hard disk capacity = cylinder number * head number * sector number * 512 bytes. According to the formula, the more the sector number is, the larger the hard disk capacity will be.