Same files in same folder (FTP)?

Question

Backup

Good afternoon!
I often come across the fact that when downloading site files via FTP or unpacking the archive, I write warnings about replacing files. It turns out that in the same directory on the server there are two files with the same name and different date of modification.
Who knows what could be causing this bug. And do I need to replace the duplicate file?
Hosted Unix, unpacked on Windows.

Answer 1

Good afternoon.
I think the reason is that on Unix filenames are case sensitive (by default), while on Windows filenames are case insensitive.
For example:
Filename and filename are 2 different files for Unix, one file for Windows.

Answer 2

There is another option when unpacking - a tmp file is created with the same name, after unpacking it breaks, something else is unpacked, and again starts unpacking that file. I've seen this many times, I didn't pay much attention to it. And I met where it is known in advance that the file names are unique (regardless of case).