Posted on : 09-08-2011 | By : stargaterich | In : Storage, Technology
Tags: computer hard disk, data storage, hard disk drive, HDD
One major component in all computer systems the hard-disk. The computer hard disk a.k.a hard disk drive better known as ‘HDD’ is the primary medium that serves as the main data storage to store all the files and programs that you have ever downloaded and installed in the computer.
Why is it called ‘hard disk drive’ ? Well, some said that it is term as ‘hard’ because the media (where the data are recorded ) is made up of rigid hard material substance thus the name hard disk drive. Gone are the days of ‘soft drive’ better known as ‘floppy disk drive’.
Anyway, HDD technology has come a long way since. HDD comes into two major form factors namely 3.5 inch and the 2.5 inch. The former is usually found in computer desktop while the latter is usually installed into computer laptops and notebooks.
The standard storage capacity for the latest generations of 3.5inch drive is at least 1TB (pronounced as one terabyte). Notebook 2.5″ HDD with capacity of 1TB has just begun shipping and you can no doubt find it computer retailer shops by end of this year.
If all these sounds too techie too you don’t worry, you will get the hang of it soon, so continue to read this post. The higher the drive capacity the more information you can store into it. Modern operating systems are getting bulkier and require more and more disk space to install. Unlike the days of DOS, nowadays, it is not surprising for an OS to take up at least 2GB or more disk space.
It is not uncommon for people to download tons of video, music and files from the Internet to their computer. Your computer disk drive or HDD can fill up pretty quickly particularly with high definition video streaming and other high resolution graphic intensive applications which churns out tons of data per second.
One of the major bottleneck with regards to computer performance is the hard disk drive itself. Even though computer CPU speed is getting faster with successive generation of new chip sets, the same cannot be said of HDD. The reason being that HDD technology is constraint by myriads of technological hurdles from mechanical and electrical aspects.
At some point of time I am sure will experience noticeable long time for your computer to start up and become responsive to your mouse clicks. Slow Windows boot up time is not surprising and the situation gets worse the longer you used the hard disk . It does not matter if you have a fast CPU, it takes time for the HDD to spin up and get ready to transfer data to the host (computer)
In a nutshell you can visualize a HDD resembling the old style music record player where you have the major components such as the record itself where the songs are stored and the playback head mounted on top of the record player which you need to manually position on the record before you on it . When power is applied to the record player, the record which is mounted on a spindle spins and the head moving along the spiral tracks pick ups electrical signal which is then further process, amplified and output as audio playback sound.
As you would’ve noticed, there are overheads in terms of the time needed to spin up the drive and mechanical movement and positioning of the head to the required track, usually in the order of milliseconds compare to nanoseconds for CPU (the computer brain, namely the microprocessor) thus this increase the operating system boot up time to get ready.
There is another class of data storage called solid state device, better known as SSD. Such storage do not contain any mechanical moving parts which obviously helps to improve computer boot up time. The major disadvantage with SSD is that it is very expensive in comparison with the HDD. The cost of the SSD increase significantly with increase capacity whereas it is not so with HDD.
One way to mitigate the shortcomings of HDD (due to mechanical constraints and overheads ) is by incorporating an SSD to store frequently used data and other critical operating system related files such as window registry and etc. Disk drive with on board SSD is known as hybrid drive.
Hybrid drive is more expensive compare to the standard HDD but a lot less expensive compare to SSD. Such drive improve computer boot up time significantly because the operating is able to boot up from the SSD portion and execute without having to wait for the drive to get ready (takes about 3 to 5 seconds for the drive to spin up to speed) and several seconds or more to move the head (seek operation in technical term) to retrieve required information.
You can get some more information by checking out this article on hybrid disk drive.