Hi special this is one of the finest question i first encountered when i purchased my laptop, i practically ate brains of my lectures to get answer but they never actually gave it. By the way here is your answer.

Actually every file and folder in system is represented in form of pointers pointing towards that file and folder. File is copied to the empty space on hard disk wherever the space is available. So the view of files and folders is not easy in hard disk as we see it in GUI. Main reason why we always need de-fragmentation.

When you perform quick format, all the format does is remove all pointers for files and folders leaving data as it is to be overwritten and hence you are able to recover each and every file as it is along with its name and extension if you want to recover form a quick format partition.

When you choose format option it reallocates partition you choose for format and writes new size allocation on it so all pointers to files and folders gets lost and also some times their extensions, data still remains as it is without name and extension and you are still able to recover each and every file (not in a folder since allocation size gets re-written), the only difference is that this time you will not get name and extensions.

You can use any recovery software to recover files. Hope that's clear. Happy Computing.

Upto i know during full format it also replaces system files

Am i right?

goyal420

Upto i know during full format it also replaces system files

Am i right?

Do you mean file system.

@ leo yeah

Yes it replaces complete file system.

@leo
What about the pointers representing the file and the folder ? in Full format???

And really very thanks!
it is really a nice answer......

@leo
taking the discussion further what is defragmentation??? i guess arranging of files?

Buddy file system is nothing but a way of arranging data in storage media.

Consider some file system XYZ has been given 100 KB hard disk to store data. Now XYZ does not actually store data as it is given to it. XYZ file system will break 100KB storage space into 10KB each, and each of this broken space will be known as cluster. Now file system itself will need some information to store about file pointer and itself in each cluster, suppose it takes 1KB so the remaining 9KB space will be known as allocation size. So from 100KB of storage only 90KB of space will be available for actual storage(reason for why your actual size of Hard Disk appears less in properties because system only shows actual storage space available).

Now you want to save some file with name abc whose size is 74KB, this file will be broken into chunks of 9 bytes and will be stored in each available cluster, please note that till 8th cluster, clusters will be filled completely but 9th cluster will be left with 7 bytes unallocated and no further data can be added to that cluster. The first cluster will store info about from where file begins(pointer to file) + name of file + file system information. And last will store where the file ends which started with pointer of first cluster. What folder really does is just hold address of pointer location where your file is present on Hard Disk in above case it is cluster 1. Till pointer holding entities are there you can see names of file appearing on your screen once pointer holding entities are removed you think file is deleted, nothing else, so files are recoverable until gets overwritten.

Now de-fragmentation when you save file in HDD it gets stored just next to any file if space is available. So suppose some file system has allocation size of 10KB and you want to store a file pqr of 50KB but 10KB space is available beside each 10KB then your file will be stored as 10KB 10KB 10KB 10KB 10KB 10KB10KB 10KB10KB 10KB where bold letters shows chunks of the pqr file distributed all over storage space, this is logical scenario of file fragmentation, the original scenario may differ with respect to file system, its allocation size and size of file you want to store. Now the process due to which all these fragmented chucks of files gets arranged beside each other properly is known as de-fragmentation.

Above things happen because your OS continuously creates and deletes temporary files. Some times even we delete some small files and then place a big file in storage media. Your system remains super fast for some time after installation because each and every file is placed properly beside each other so system never needs jump from one cluster to another because next cluster is beside the previous one and as you start using it for longer time several temporary files, that gets created, change the original file setup and you need several tools to remove them, and then de-fragment but once changed scenario never returns since even when you are applying tweak, temp files are created and deleted so even after applying those tweaks the performance of just after installation is never attained.

Hope that was quit easy explanation. Happy Computing.