I can’t think of any other symbol that it could be confused with so can any Dopers please satisfy my curiosity?
My handwriting stinks. If I don’t cross my 7s they look like 1s. Picked it up a long long time ago after seeing my Prussian great-grandfather’s handwriting - his 1s and 7s looked exactly alike except for the cross.
Agreed. Some people write their 1’s with a downstroke, in order to distinguish them from I’s and l’s, I imagine. This is especially common in Europe.
I cross my zeroes, also.
My handwriting is even worse than my grammer and spelling. I don’t cross my 7’s though. I DO cross my Z’s. I’d guess the people that cross things do it out of a learned habit. I picked up the Z crossing thing from high school algebra so as not to confuse 2’s and Z’s.
Crossing 7’s Z’s (only capital) and writing 1’s with a downstroke is the default way writing is taught in German schools. I guess this is the same in most of central Europe. So it’s not just a habit.
I was in the Personnel Automation field during my stint in the Active Army. We were taught to write certain letters and numbers in a way that couldn’t be confused on a code sheet.
One - vertical line with an underscore. Looks like an upside-down T. Like this: [symbol]^[/symbol]
Seven - cross with a horizontal bar through the middle. I was told by my dad that this was a German thing, who knows?
Zero - vertical ellipse with a foreslash. 0 and / placed on top of each other.
Capital Oh (O)- underscored circle.
Capital Ess (S) - underscored. To differentiate it from 5.
Capital Zee (Z) - crossed like 7. To differentiate it from 2.
blank space - A b and / on top of each other.
I still write like this when handwriting stuff (I have horrible handwriting) 10 years later.
I know why I do it. Because in third grade the teaching assistant in my class was a Swedish exchange student or something ( hey, it was third grade, I wasn’t up on the details 
) and idly commented, after thinking I had crossed a 7 when I had just made a semi-scribbled seven, that it was a European thing to do. I thought that was just neat at that tender age and started doing it deliberately. Z’s too. Now it is just habit :).
- Tamerlane
I won’t cross a seven because it eight nine.
I just had to, I’m sorry. Moderators, please feel free to delete this post if the corneyness of it is too potent.
Carry on!
Seventh grade algebra, that’s why.
Well, in my case at least. Z and 0 (zero) too.
I use $ for S.
We were taught to do it in Algebra class so that it would not be confused with Zs
I cross my 7s and my lowercase zs. I do it because I like the way those characters look that way.
I picked it up about 10 years ago, when I was 15. Unlike my other attempts to change my handwriting, this one stuck with little conscious effort.
This is only halfway related, but it might be worth sharing:
I install car alarms and remote starters for a number of car dealers, and I spend a lot of my time at this one Toyota dealer.
Their new Toyotas carry a stock number beginning with T. For example, it might be T1234. Used cars start with P, for “pre-owned.”
Sometimes, they’ll end up swapping cars with another Toyota dealer, in order to get the car their customer wants…I had to ask someone to explain why their swap cars had stock numbers like 1234$. Makes sense now.
I do it because (a) I was taught to, and (b) I’ve done enough data entry jobs where people’s handwriting on application forms was dire. You’d be surprised how easy it is to make a 1 look like a 7.
I cross my z’s because of high school algebra. I cross my 7s because it’s european and I wanted to be different than other people.
I read a news item once about a state government employee who was fired from his job because he was told to quit adding the crossbar to his 7s. Because they were trying to standardize government employee handwriting or some such idiotic crusade. He continued to cross them and was fired.
I heard TV interviews of other cops at that place talking about him. THey did not like the crossing of the 7’s because it struck them as something a furriner would do so they made up that thing so they could fire him.
Back when I was a SIDPERS clerk, Horseflesh, I got the same number writing instructions you did with one addition: the S also had an underscore to distinguish it from a 5.
Thanks, lee. I knew I hadn’t imagined the whole thing. So it was just good old American knownothingism (xenophobic bigotry).
I have used the crossbar on 7 and Z most of my life, too. I self-consciously started to do so because letters from my cousins in Italy had them, and I observed the practice when I went to France, so I adopted it to be more cosmopolitan. But then it became just a habit.
I think of it as a “moustache.”