It has been a while since we last talked or written about trailing slashes in your URLs and how it may or may not impact your rankings with Google. But hey, since Google's John Mueller brought it up both on Google+ and Twitter, let's get into it again.
In short, John explains that it isn't how Google handles the trailing slash for the most part, instead it is how servers treat them by default. That being said, John Mueller explained "the slash after a hostname or domain name is irrelevant, you can use it or not when referring to the URL, it ends up being the same thing." "However, a slash anywhere else is a significant part of the URL and will change the URL if it's there or not," he added.
He even made this nifty chart to try to explain it better:
He even posted this example of how the Google robots.txt file at http://ift.tt/1NSs1Wg works fine but http://ift.tt/2CFtawi 404s.
John explained, as I said above, "this is not SEO-specific, but just how websites work."
Forum discussion at Google+ and Twitter.