How to prevent OS X from creating 'ghost files' on external sources??

[The_Prodigy1982]

Whenever I copy files from my iMac towards any external source (no matter if it's Dropbox, or an external harddrive/usb stick)... the system creates what I like to call 'ghost files'.
These files are empty files, named exactly the same as other files within the same folder I just copied.

For example, if I copy a folder with files named 1, 2 & 3 from my iMac to an external usb stick... that external usb stick will have those original copied files in the newly created folder, BUT there are also 3 empty ghost files with the exact same name.
These ghost files however always start with an ._ or ._. extension before the actual filename.
So the newly copied folder on my external source would contain 6 files in total; 1, 2, 3, ._.1, ._.2 and ._.3

- Does anyone recognise this weird ghosting issue??
And what to do about it?
Is there any way to fix this, so that OS X doesn't create these ghost files in the first place??
These ghost files normally ONLY appear when viewing them from OUTSIDE my OS X environment (so when I access my dropbox account using my iPhone for example, OR when I plug in my usb stick in a Windows PC).

I assume I'm not the only person with this issue??
* I have this ghosting issue ever since I got my iMac (August 2015).

 

[Just_Me_D]

Emptying the trash bin typically fixes similar problem, but if those files only appear when viewing them from outside of OS X then I don't know what to tell you. Hopefully, someone who does will reply soon.