HOW Hard drives Work

HOW Hard drives WorkMatas Caamao pablo Caamao alejandro rizzi

https://www.youtube.com/watch?v=3owqvmMf6No1INTRODUCTIONA hard disk drive (HDD), or hard drive is a data storage device used for storing and retrieving digital information using one or more rigid (known as "hard") rapidly rotating disks (platters) coated with magnetic material.

The first Hard Disk was introduced byIBMin 1956.

The primary characteristics of an HDD are its capacity and performance.

https://www.youtube.com/watch?v=3owqvmMf6No2HARD DISK PARTSThe hard drive is composed of several parts:

ActuatorRead-write armCentral spindleMagnetic platterPlug connectionsRead-write headCircuit board (on underside)Flexible connectorSmall spindle

https://www.youtube.com/watch?v=3owqvmMf6No3

HARD DISK PARTSActuatorThe actuator is the responsible for moving the read-write arm.

Read-write armArm where the read-write device is placed.

Central spindleAllows platters to rotate at high speeds.

https://www.youtube.com/watch?v=3owqvmMf6No4HARD DISK PARTSMagnetic platterWhere the information is stored in binary form. 1 to 10 identical platters.

Plug connectionsLinks the hard drive to the circuit board in the computer.

Read-write headIt Is a tiny magnet on the end of the read-write arm, responsible for reading and writing the information in the platters.

https://www.youtube.com/watch?v=3owqvmMf6No5HARD DISK PARTSCircuit board Controls the flow of data to and from the platter.

Flexible connectorFlexible connector carries data from circuit board to the read-write head and platter.

Small spindleThe small pindles allows read-write arm to swing across platter.

https://www.youtube.com/watch?v=3owqvmMf6No6How it worksData on a hard disk is stored in microscopic areas called magnetic domains on the magnetic platter. Each domain stores either a 1 or 0 value (Binary).

The platters spins at an extremely high speed, technically between 5,400 to 10,000 revolutions per minute (RPM)

The head hovers very closely to the platter. The RW head suspends on a thin cushion of air which the spinning platter induces.

The sliding motion of the RW head is derived by passing a current through the coil which is part of the actuator-assembly. As the coil is placed between two magnets, the forward or backward sliding motion is hence derived by simple current reversal.

https://www.youtube.com/watch?v=3owqvmMf6No7As the head writes data onto the disk, it changes its magnetic polarization to induce either a one or zero value.

During a read request, data is interpreted when the magnetic fields on the platter brings about an electrical change (as a result of change in electrical resistance of some special material property) in the read-head that passes over it.

These electrical fields are then encoded and transmitted to the CPU to be processed and read by the system.

How it works

https://www.youtube.com/watch?v=3owqvmMf6No8When the computer is switched off, the head is usually pulled to a safe parking zone:

A lifting mechanism parks the head outside of the platter onto a "parking bay" prior to a shutdown. It then automatically unparks and relocates itself above the disk platter when the platter spins up to appropriate rotational speed.

Prevents the head from scratching against the data zone on platter when the air bearing subsides.

How it works

https://www.youtube.com/watch?v=3owqvmMf6No9

Solid State drivesUses a type of memory called flash memory

SSD memory remains even when it loses power

Uses a grid of electrical cells to quickly send and receive data.

10 Times faster than normal hard drives because it doesnt need to spin a platter or locate a RW arm in the right position.

https://www.youtube.com/watch?v=3owqvmMf6No10