how does a computer physically delete something, will it not always be there?

Answer 1

when you delete a file, it actually removes the directory info so it appears not to exist, it is still on the disk however until the physical space it is on is overwritten with new data

Answer 2

Usually when you delete a file, it does not get physically deleted from the disk. The opertaing system (Windows), keeps a lookup table that tells it where on the disk is each existing file. When you delete a file, the only thing that happens is that this file's entry is deleted from the table, and the disk space it has occupied is reclaimed by the operating system for future use. That is the reason that various undelete programs that restore deleted files can work - instead of using the lookup table to find out where the file is, they search for it using other methods. Of course those programs will not work forever - at some point the operating system will use the disk space it reclaimed and the file will be lost forever. For more in-depth information, have a look at http://en.wikipedia.org/wiki/File_Allocation_Table

Answer 3

Butchell is right. Windows doesn't actually remove the file, it only removes it from the drive's File Allocation Table (it's index, in other words). Windows XP uses a different system, but it still has an index, that tells the processor where each file is located. That's why it's possible to use software to recover recently deleted data, unless the area where the file resided was written over multiple times.

Answer 4

unfortunately i am not exactly sure how modern operating systems work but i think the information is permanently deleted. but one of the great things about DOS was that when something was "deleted" the information was basically classified in a manner that would allow it to be written over. so if there was still empty space the file could stay on your computer for several months and there were relatively easy ways of recovery recently deleted information.

Answer 5

when a computer delete something from the hard drive it just re-classes it as free space, until other data is written over it it will always remain. For businesses and people concerned with security they normally get a wiping software that overwrites free space with a pattern of 1's or 0's, The more times the space is over written the more secure the wipe current standards are:
The normal user 1 -3 passes of a wiping software
business users with sensitive data at least 6 passes
Government or military computers at least 35 passes

Answer 6

when deleting a file the operating system just drop the address of a certain file, and be aware THERE IS NOTHING CALLED EMPTY in computers...empty means zero, although zero and one is the only values on your ram and harddisk, it is just deleting the address of the file...so the operating system will remark this area as writeable for another new files, however if you want really to check it, try to install any undelete software...it will get the deleted files, because it looks for the deleted addresses not the deleted files...in conclusion you can get them back

Answer 7

In the first instance a computer puts a tag at the start of the file to say it is deleted. It is not completely gone till it is overwritten with new data.

Answer 8

you can download a program called 'shredder' or something which when used to delete a file, deletes it and writes over it so the original file is now non-existent.

Answer 9

it depends on ur deletion request, if u just move ur files to ur recycle bin, then u can still get them back whenever u need by accessing the recycle bin and choosing the file then restore it.

but if u chose the option to delete the files permenantly, then say good bye to the file, u won't be able to get it back.

Answer 10

Well what i learned from watching Navy ncis is that it isnt necesarilly deleted.What does happen is it gets stored in your magnetic harddrive and when deleted it actually gats written over.