A couple of questions.

[I_Zeratul]

Hello everyone, this is kinda my first post here. I usually post on reddit, but I wanted to check out the community here. Sorry for getting straight to the point. I am a third year computer science student. I have been reading a lot of computer science stuff lately and I have a couple or questions. If you have the time and want to answer, I would be very grateful. Here we go:

1) Why are nearly all hard disk storage devices (used in PCs) I have seen classified as IDE or SATA drives (From what I heard IDE is not used nearly as much today). Are they the best around, if so why? I have read some stuff on wikipedia but I don't understand a bit of the technical vocabulary used there.

2) Who decides whether a hard disk storage device will use an MBR partitioning scheme or a GPT partitioning scheme. For example I have only worked with the MBR partitioning scheme. I wanted to practice partitioning with GPT, but none of the hard disks I have use GPT. What can I do about that, just theoretically study the GPT partitioning?

3) During partitioning, using Gparted or some other partitioning software I have seen some unusual terms (unusual for me that is) like cylinders and sectors. From what we studied physically a hard disk is composed of tracks. Every track consists of 2 components: blocks(sectors) and gaps. All tracks of every disk in the disk compartment with the same radius from the center compose a hypothetical cylinder. A cylinder is an important term because the heads of the hard disk can read simultaneously from all tracks of a cylinder. Can someone confirm what I just said and if it is true why are these terms mentioned during partitioning. Another interesting thing I read is this: Wikipedia says that the first sector on a partitioned hard disk is called the MBR boot sector. Which sector is the first sector physically and what does that mean in terms of memory? Does that mean that, for example, the first 50 KiB (Do note the number is random, given by me) of a hard disk compose that first sector or something like that and I am not able to use these bits to save my own data.

4) What is the purpose of a RAID configuration? From what I read I think it is sometimes better than having just multiple partitioned hard disks because it improves performance (read/write operations) and handles disk failures and errors more efficiently.

5) If I manage to make a RAID configuration for example with 2 hard disks in a linux-based OS. Will I see something like partitions. For example I merge sda1 with sdb1 partitions (the first primary partitions on both my hard disks) into 1 volume. Will I be able to create folders, save my pictures, videos, music like I do in my partitions, just instead of partitions here I work with the volume ignoring the underlying partitioning layout and the OS knows how to distribute the files on the underlying hard disks. (depending on the RAID level).

I am sorry I am a bit of a newbie here, I am trying to improve my knowledge and the only reliable source I have for this stuff is forums and wikipedia (haven't found any good books about this).

Also, sorry that this is very long, I just needed to ask. You can answer what you wish, I would be very grateful for it.

Thank you in advance,
a computer science student

Edited January 19, 2015 by I_Zeratul

[LaurieAG]

Hi I_Zeratul,

 

Wikipedia has some good information and the 2 links below cover over half of your questions.

 

http://en.wikipedia.org/wiki/GUID_Partition_Table

http://en.wikipedia.org/wiki/Parallel_ATA

[Strange]

1) Why are nearly all hard disk storage devices (used in PCs) I have seen classified as IDE or SATA drives (From what I heard IDE is not used nearly as much today). Are they the best around, if so why? I have read some stuff on wikipedia but I don't understand a bit of the technical vocabulary used there.

 

I am not that familiar with the history (or even implementation) of these interfaces but most of the choiuces in interconnects are driven by technology. When IDE was developed, the fastest way of transferring data was in parallel over a number of data signals. More recently, serial interfaces have got faster and more reliable (partly because electronic components have got faster and also because new encoding schemes have been developed to exploit that) so that many interfaces and busses that were parallel previously have become serial. Serial means fewer wires which means lower cost and lower power.

 

Found a brief history of IDE here: http://www.pcguide.com/ref/hdd/if/ide/over-c.html

Edited January 19, 2015 by Strange