I remember a typing teacher being very serious about two spaces after the dot[1]. He was also serious about the letter O being an acceptable substitute for a zero "0". Fortunately both of these rules are now firmly in the past along with witch burning. This is progress.
[1] yeah, I could call it a period or a full stop. But its also a dot. Variety is the spice of life as is properly finishing your
Yes, I remember double-spaces between sentences from "Typing" class in Junior High School (you know, before they even offered anything called "Computer Science").
Type-set lead blocks allowed for variable spacing, typewriters were more limited. When I see double-spaces now (in email, for example) I tend to draw conclusions about the sender's age.
Can confirm. Also learned that in 1988 in my typing class. Also learned lower case l instead of a 1. It was for typing speed so you didn't have to reach for the top row.
Features of the typewriter I used in the 1970s as a kid (which was old even then):
(1) Did not have a "0" key. Use capital letter "O".
(2) Did not have a "1" key. Use lowercase letter "l".
(3) Did not have a "!" key. Type ".", then backspace, then type "'".
The typeface was designed to make this work well. The "l" looked close enough to a "1". The dimensions of "." and "'" were such that they fit together, and "'" did not have any curve to it that would look out of place on an exclamation mark.
(4) Had a cent sign in addition to dollar sign. This was nice because the symbol was used a lot in real life.
(5) Had a key to type 1/4 and 1/2.
(6) No backslash, of course. Which explains why old people mix this up so often. They aren't accustomed to there being two different ones they need to keep straight.
(7) That LOCK key above SHIFT physically locks the SHIFT key in the down position. I'm not sure what you'd call the mechanism, but it's something like a pawl. SHIFT would normally spring back up, but this blocks it from doing that. You push SHIFT down further to release it.
(8) You can load the typewriter with a ribbon that has red and black ink. (You can see red in the photo above.) There's a lever toward the right that controls this.
(9) There is no enter or carriage return key, of course. The whole carriage (top part that holds the paper) moves side to side as you type. The power comes from being spring loaded. When you want a new line, you grab that shiny lever at the top left and yank the whole carriage to the right. So you are returning the carriage to the start of the line.
(10) Note the TAB SET, TAB CLEAR, and TABULAR buttons. These work like a tab key on computer. You move to some column, push TAB SET, and it remembers that position mechanically. When you hit TABULAR, it moves to that position. Since the carriage is spring-loaded, this is quite lively. The carriage is metal and heavy (a few pounds?), and when you press TABULAR, it gets moving pretty good, and it slams pretty hard into the tab stop.
(11) The platen is the roller that the paper wraps around. You can see a knob on the left and the right that can be used to turn the platen. It turns in steps corresponding to the height of one line. But the button centered in the left knob lets you release that and turn it continuously. So it's kind of an snap to grid function that you can turn off and on. You can use this for typing superscripts and subscripts or other weird effects.
[1] yeah, I could call it a period or a full stop. But its also a dot. Variety is the spice of life as is properly finishing your