Why do we put underscores in file names?
Why do people tend to put underscores between words when naming a file?
Answers:
Immmmmmmmmmmmmmm...you'r question underscores the answer!!??.
When a file or folder is created, there are limitations to use charecters such as # or @ or & etc.,. Either use plain words or words and numbers combination or just use two words like a first name and last name. In this case, to make it clear that there are two names, you can use an undderscore, because the file creation tab will accept underscore.
An empty space between words does not look good on the file name, long file name is very unprofessional, therefore, use two small meaningful words and separate them with underscore.
Other answers:
In the dark ages you couldn't use spaces in file names and it is easier to read if you break the words apart. The next best thing to use was an underscore.
So the file appears to be an human readable by using underscroe instead of space.
Also some program/system doesn't like space in the file name.
BECAUSE THE FIRST COMPUTERS THERE WERE NO SPACES
for better readability.
This started when you can't have a space in filenames.
Because it is a representation of a space.
Some Operating Systems don't recognize the space character Something like DOS file names being in the 8.3 format. And of course, readability and convenience is also a factor.
If you're talking about files saved to be uploaded to a web server, it is better to do so because when you put a space between words, it translates it into the percentage sign %.