How do computers change information? If I understand correctly,

Files on the disk are stored fragmented in little pieces. The correct location of the file is cataloged via the filesystem, which is located on a reserved space on the disk. Where the new file will be created - depends on the file system, some take the first free spaces, others decide on other factors such as unfragmented space

>>60965725
Your operating system handles that. It has nothing to do with the storage medium.

As for how the decision is made, your operating system stores a list of "file descriptors" at the beginning of your hard drive, which have the name of the file and some metadata about it like the size and the position of the actual file contents on the disk. When you delete a file, the contents of the file aren't actually deleted, just this little file descriptor that points to the contents. This is how file recovery tools recover data. Once the file descriptor is deleted, the section of the disk that the file was stored in is marked as free, and until something else is written to it, the operating system considers it to be full of random garbage. Once a new file needs to be written, the free space full of garbage will be overwritten with all or part of the new file. If it isn't big enough to hold the entire file, the file is broken into chunks and as much as possible is written to the free sectors. Having many small free sectors from small deleted files causes files to be broken up many times, which is what fragmentation is.

>>60965835
>>60965868
Pretty interesting. Thanks a lot.

>>60965868
Why is defragging necessary on Windows but not on Linux?

>>60967086
ext3/4 don't fragment the same way that NTFS does, which makes it unnecessary.
https://askubuntu.com/questions/1090/why-is-defragmentation-unnecessary

>>60965725
It's magic.

>>60967086
because those file systems weren't written by pajeets

>>60967203
Almost. Genius is next to magic.