[Tagbert]

Do your files really not have file extensions or is it just that they are hidden by default in the file browser?

In Mac OS extensions are important but they are hidden by default. I always force them to be shown when I setup a new Mac. Hiding them obscures important information. Hiding them offers nearly no benefit.

[klyrs]

I use Linux exclusively, where file extensions are entirely optional. While, yes, they are shown in the file browser, that's a tool of last resort for me: my display is typically a grid of terminals and I do most of my work through them. Text files, such as executable scripts with shebangs, do not get file extensions. Plain text files, such as when I'm taking notes about something, do not get file extensions. Stuff like images, music, etc get file extensions.