Spaces between sentences

I was never taught to put two spaces after the period. But early in college, when a friend was watching me type up a paper (yeah, osnap, caught in the act of actually doing homework: I hate that), he went: "You don't put two spaces after your sentences?!" I figured it was just a sly trick to get just that little more to the length of your paper, then I realized it seemed to be the norm among everyone else I knew; so I now put two spaces in paper and things. Then again, in documentation and stuff I do at work, I haven't been putting two spaces since it the people there don't seem to do that as far as I've seen. When in Rome, amirite?

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