For the last 25 years ever since our first Microsoft Me computer in 2000, I have always labeled my files and folder with plain English sentences using words with spaces like a normal human being would tend to use. I also notice that everything I download uses the underscore character to eliminate spaces and form one long strung together word name. Have I been doing it wrong all of these years? It doesn't seem to have had a detrimental effect on my really bad filing system that I can detect.
50 years ago I took a Fortran 4 computer class using punch cards and printout sheets. Each time I ran the program I was trying to write I would get a bunch of errors. After fixing the errors with more punch cards, I would get more errors and add more punch cards. Nothing I ever wrote ever worked but somehow I got a C in the class anyway. It must have been for effort.
I said to myself that these things suck and I would NEVER have any reason to use a computer in my life and there was no reason in the world to continue trying to figure them out. But alas, now here I am... 
If you are using a DOS operating system computer, then yes. Otherwise, no.
There are some character use restrictions on file names, but spaces is not one of them. I personally find it hard to put periods in file names, but those are allowed (mostly).
-
The forbidden printable ASCII characters are:
-
Non-printable characters
If your data comes from a source that would permit non-printable characters then there is more to check for.
Note: While it is legal under Linux/Unix file systems to create files with control characters in the filename, it might be a nightmare for the users to deal with such files.
-
Reserved file names
The following filenames are reserved:
-
Windows:
CON, PRN, AUX, NUL COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9 LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9
(both on their own and with arbitrary file extensions, e.g. LPT1.txt).
-
Linux/Unix:
. (special name referring to current directory) .. (special name referring to parent directory)
-
Other rules
-
Windows:
Filenames cannot end in a space or dot.
-
macOS:
You didn't ask for it, but just in case: Colon : and forward slash / depending on context are not permitted (e.g. Finder supports slashes, terminal supports colons).
You sometimes see underscores used instead of spaces because they're a little more convenient in web URLs (where a space becomes %20), they can also be a little more convenient for access via some CLIs where spaces need to be escaped. No reason to change your own file naming.
IStillUnnecessarilyCapOutOfHabitButNeverGotIntoUnderscore
Spaces can cause problems in some systems as they're not always treated the same way and some systems require them to be replaced with an escaped character. They're also not valid in URLs, aka web addresses, which is why you'll rarely see them in files you download. As a bonus, my_file_name is easier to read than my%20file%20name or my\ file\ name or even my+file+name
For home use, youre fine using spaces. The problem is URL's cant have space, so the space is referenced as %20. So when you download something, the URL is more manageable with something like + or _ than %20. I also recall URL had a 256 character length, so a bunch of spaces add up depending on the file structure of whats being shared.
Keith Tanner said:
Spaces can cause problems in some systems as they're not always treated the same way and some systems require them to be replaced with an escaped character. They're also not valid in URLs, aka web addresses, which is why you'll rarely see them in files you download. As a bonus, my_file_name is easier to read than my%20file%20name or my\ file\ name or even my+file+name
Yeah, if you are working in sharepoint, %20 gets annoying, also reaches the 255char limit faster than _
This is unlikely to matter to most people, but if you ever want to manipulate your filesystem using a command line and scripting tools then putting spaces in your file and directory names will make it harder. Not impossible, just harder than necessary.
I still fight this, given that my earliest regular computer use was with DOS 5.0 and Win 3.1. I'm still hesitant to use spaces when naming files.
In reply to VolvoHeretic :
I took that FORTRAN class and I too got a C.
Sometimes my computer desktop system makes me feel like I'm pigpen from Snoopy.
We use Title Case (not Strict Title Case where articles, prepositions, and conjunctions AREN'T capitalized) plus underscore for our XML file names in our version control systems. Previously used PerForce, now we use GitLab.
I use underscores. Off the top of my head, this makes at least two things easier: blasting around the OS using command prompt, and creating hyperlinks.
Plus, it makes me look cool.
In reply to Datsun240ZGuy :
I wonder if my C was for the sheer number of cards I used.
I will forever remember trekking across campus in January, late at night, braving icy winds and driving snow to get to the building where the IBM punch card machines were. I'd spend hours there, and then trek back across campus, the air even colder, just so I could turn in my stack of cards and wait a couple of days to see if my program ran or not.
In reply to 1988RedT2 :
I remember that a couple of really young and smart students in the Air Force working on the Minute Man III missile launch control computers discovered that the computer emitted AM signals while it ran and wrote programs that would play popular songs over a radio. Pretty cool. I thought that I could get it to compose music by using the basic chord progression rules for rock music piggy backing on their program. Kind of an early AI. It couldn't, didn't, and wasn't. 
The college had a big main IBM computer that all the rest of the faculty and students used but I went to an "Experimental College" department that had their own suitcase IMB 1130 (I'm guessing) that we had exclusive access to 24 hours a day.
Wikipedia.org: IBM 1130
NoYouShouldJustNameFilesLikeThis - UpperCamelCase (or PascalCasE)
In the early 80's I worked with a dude who went to UICC (guess that one) a few years after his brother did.
Both engineering majors - the school was getting rid of a giant mainframe so the brother converted his moms garage - added some extra transmitter in the yard and had it moved home.
Not sure what his plan was - always wonder if he made money off the effort. UICC = Univ of Illinois Chicago Circle.
In reply to Datsun240ZGuy :
I've heard of someone doing that a few years ago just as a hobby with a recent IBM mainframe. It's a powerful computer that can run z/OS or a couple of Linux distros but it has a z/Architecture CPU, so there's nothing that it's terribly useful for to a home user, and it sucks down many kilowatts of power at full load (step 1 to getting it working was adding a beefy 220V circuit to the house). Last I heard he was running BOINC WCG workloads on it through an x86 virtual machine resulting in terrible efficiency.
Beats cryptomining at least...
I think this thread title has broken the zoom layout on my phone. I'm not going further than having tried the next page back of Latest Topics to verify, but that's what it looks like to me.
If I pinch to zoom out on other pages it snaps back to fill screen width. This thread and the forum page that contains it... not so much.
GameboyRMH said:
I've heard of someone doing that a few years ago just as a hobby with a recent IBM mainframe. It's a powerful computer that can run z/OS or a couple of Linux distros but it has a z/Architecture CPU, so there's nothing that it's terribly useful for to a home user, and it sucks down many kilowatts of power at full load (step 1 to getting it working was adding a beefy 220V circuit to the house). Last I heard he was running BOINC WCG workloads on it through an x86 virtual machine resulting in terrible efficiency.
Back in the 90s when I shared a house with a bunch of other current/former student/nerds, we talked about getting a VAX 11/750. Biggest problem was that it needed 3-phase power, and that was very expensive in the days before cheap VFDs.
Mr_Asa
MegaDork
1/21/25 7:11 a.m.
Jesse Ransom said:
I think this thread title has broken the zoom layout on my phone. I'm not going further than having tried the next page back of Latest Topics to verify, but that's what it looks like to me.
If I pinch to zoom out on other pages it snaps back to fill screen width. This thread and the forum page that contains it... not so much.
You are correct. It borked something.
Hopefully this fixes it
Jerry
PowerDork
1/21/25 8:28 a.m.
First computer in the early 80s, both home (VIC-20 and C64) and at school (giant Honeywell mainframe for "Business Data Processing and Accounting").
I sometimes use-dashes-just-in-case. But you can pry the 100mb Zip drive out of my cold dead hands before I stop double spacing after each sentence.
