When I learned to write, the capital J (and it starts my first name) had a line across the top.
The letter Z (lower and upper case) had a small line through the center. The numeral 7 had a similar line through the center.
My wife and I are having an argument about this. She thinks I’m crazy. She’s right, but not on this point.
Any help?
I don’t know about the line across the top of J’s but my mom does the line through Z’s and 7’s and I’ve picked it up from her. I believe it is done to distinguish Z’s from 2’s and 7’s from I’s and T’s more readily. I could be wrong.
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I draw my sevens and z’s with a line. J’s can definitely be drawn with a bar across the top.
I attended elementary school in the forties and never saw this until later. I remember it as a european habit, perhaps even originated by the french. I can’t provide any proof though.
In certain fields, like engineering, it’s common to put a line thru Z’s so you don’t mistake them for 2’s. Part #475Z and Part #4752 are probably not the same part, and you don’t want to mistake them.
I’ve seen sevens written with a line thru the mid-section, but that seems to be pretty uncommon these days. I guess they probably wanted to make sure you didn’t mistake 1 and 7, but that doesn’t seem to be a problem for anyone I’ve ever known.
I thought the J with a line was just a style that certain fonts chose. The one I’m typing with now does it.
AFAIK, FWIW…
I believe the number 7 is drawn with a line through the middle in most European cultures (including British) – but not in American. I draw mine with a line.
I’ve never seen (nor, obviously, written) an uppercase J without a top-line.
ETA: Well, the display font here seems to lack a top-line (although the reply-box font does have one)
I’ve seen Z with and without a cross-line, but I can’t ascribe this to any particular group or groups. I generally don’t use a cross-line in mine.
English-speaker, mostly American-centric culture-wise, living in a non-Latin-alphabet-using culture (Israel)
I was taught to draw a line through the lower case ‘z’ in math class, so that it wouldn’t look like a 2 when used in equations. Never outside of math class, though. I was taught the line through the 7 in French class. Apparently that is the European way to write a 7. It seems to be gradually migrating across the Atlantic, though.
‘0’ (zero) had a diagonal slash in many early computer systems for similar reasons of differentiation from the letter O.
I was referring to the line across sevens, and sometimes zees. I did learn to print a cap. “J” w/ a line on top, just like a cap. “T”. The small “j” was dotted, like a small “i”.
I would be surprised if this were the case - if anything, European styles of writing certain numerals are surely more threated, due to the prevalance of standardised computer fonts?
When I learned to draw the number 7. it had not only a little bar across the middle, but a little one down from the top, so it resembled a fish hook.
J with a line? Still exists in serif fonts: J
I’ve always thought of the lined 7 as a French thing, but have started doing it myself recently because my handwriting is so bad that my 7s look like 2s.
I was taught to draw a line through the 7 to distinguish it from a 1, and the Z to differentiate it from a 2.
The smiley face doting lower case i I picked up on my own.
In my experience, we wrote them plain in elementary school. In Junior High, I was friends with a hispanic group of friends, and they ALL wrote their 7’s and Z’s with a bisecting line. I thought it was neat, so I picked it up.
Later, when I started computer classes, the lines through 7’s, Z’s, and zeroes became essential to writing computer stuff out. I now do it almost exclusively, without thinking.
When I took one of my first computer classes (back in the 70’s) the instructor was adamant that the letter O should be slashed, and not the number zero. His quote, “Everybody in the world does it that way, except for IBM and the Federal Government.”
Apparently, IBM and the Feds had more clout than my instructor in the long run. 
I don’t do the 7 thing or the Z thing, but I definitely cross the top of my J.
Heh, I’m pretty sure I first encountered it this way on a BBC Micro, who certainly weren’t bowing to either of those two!
Huh…my j’s just have hats on them…
(waits around for someone to get the “joke”)
well to really twist things up, I make a capital F like a 7 with a line through it. I got this from my Grandmother but now know of another unrelated person who does the same thing.