Make one space after punctuation the law of the land. It's not two spaces after a period, it's one. Period.

Now that typewriters are obsolete, the rule about inserting two spaces after punctuation is obsolete as well. Two spaces are no longer necessary because of proportionately spaced, digital fonts. All editors, proofreaders and manuals of style agree on this. Help end the wasteful use of space and the wasteful use of energy debating this issue.