Jump to content

Welcome to Geeks to Go - Register now for FREE

Geeks To Go is a helpful hub, where thousands of volunteer geeks quickly serve friendly answers and support. Check out the forums and get free advice from the experts. Register now to gain access to all of our features, it's FREE and only takes one minute. Once registered and logged in, you will be able to create topics, post replies to existing threads, give reputation to your fellow members, get your own private messenger, post status updates, manage your profile and so much more.

Create Account How it Works

Read/Write Head never actually touch the platter?

  • Please log in to reply




  • Member
  • PipPip
  • 98 posts
Hello guys, good morning. :D

Awhile ago, I'm having a research about "How Hard Disk Works?" and Google gave me the of HowStuffWorks. While reading the topic "Cassette Tape vs. Hard Disk" this line makes me curios.

In a cassette-tape deck, the read/write head touches the tape directly. In a hard disk, the read/write head "flies" over the disk, never actually touching it.

Can somebody explain this more deeply little bit. I mean, how the data is being read and write without touching the platter?

Hope somebody will give a brief explanation with this.

Edited by SHENGTON, 06 January 2011 - 09:05 PM.

  • 0


Neil Jones

Neil Jones

    Member 5k

  • Member
  • PipPipPipPipPipPipPipPip
  • 8,476 posts
The heads float on a cushion of air.

If you'd read further down the list of Google results, you'd have found this:
  • 0



    Grumpy Ol' MSgt (Ret.)

  • Retired Staff
  • 3,999 posts
  • MVP
It is important to remember that data on hard drives is stored on these "magnetic" disks or platters by arranging "magnetic" particles in such a way that they represent either a 1 or a 0. If you hold a magnet just off a refrigerator door, you can still feel the pull without the magnet actually touching the door. The read head works the same way. It moves over the magnetic particles and "feels" the pull and determines the alignment.

Magnetic tape works the same way but remember tape is ancient technology. The magnetic particles on the tape are the size of mountains compared to those on a disk. And it took a lot of magnetic power to move those mountains so the tape heads (also of ancient technology) were also huge and no where near as precise. To ensure the tape head only moved the mountains it needed to, it had to get in close. But it still did not actually touch the magnetic particles of the tape, it touched the layer of smooth material, typically polymer.
  • 0

Similar Topics

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users

As Featured On:

Microsoft Yahoo BBC MSN PC Magazine Washington Post HP