You might be old if…
You might be old if you include two spaces after a period. This was the norm when we used type-writers, and we carried it over to the computer keyboard. With the character limitations of Twitter and even LinkedIn, the extra space became a waste of useable communication space. And think of all the paper that could be saved by eliminating that extra space.
The extra tap on the space bar is just one very small habit that we can easily see—especially when that period hits the end of the row in an email and the next line begins with a space rather than a clean left justification. What would it be like to watch that one habit for one week? What other habits would you start to recognize?
It’s not a harmful habit (except the paper—why do we still use paper?). Really, it’s not about the space, it’s about the habit. Are we mindful enough to recognize what we are doing and why we do it? Make it a regular practice to mindfully examine our way of doing things and make conscious choices to continue the practice–or not.
By the way, Chicago Style Manual actually tells us that two spaces after punctuation is wrong.