Just wondering what is the purpose of the other file that is created with blender. It takes up the same disk space. Is it ok to delete it? Is it like an autosave file similar to ones Nuke produces?
The .blend file is the file that you last saved. The .blend1 file is the saving you did before the last saving. You can have plenty of these files so you can save your previous savings.
Basically when you save you project the .blend turns into .blend1 and .blend1 turns into .blend2 and so on.
You can use them by renaming the extension to .blend
You don't show the extensions for the file, that would help explain.
Depending on the settings you are using to save, blender renames the previously saved file as .blend1 and the new saved file as .blend.
So the other file is kind of a backup, it is the last saved version of your project.