Oh, how I love this little symbol. If it were a key on my laptop keyboard it would get a fair bit of use. Those occasions when you type something that asks a question in an excited manner, a rhetorical question, or is a statement of disbelief in the form of a question, for instance ‘You’re pregnant?!’ … ‘It was how much?!’ - how much more satisfying it would be to be able to type an interrobang at the end.
 
An American, Martin K. Speckter, conceptualized the interrobang in 1962. He was head of an advertising agency and believed that advertisements would look better if copywriters conveyed surprised rhetorical questions using a single mark rather than a question mark (interrogative point) and an exclamation mark or point (known in printers' and programmers' jargon as the "bang").
 
If you are using Microsoft Word, you can type an interrobang by switching to Wingdings 2, holding shift and typing 6^. Sadly I think the only way to use it on social media (at present) is to copy and paste a photo. 
 
For more information on this funny little symbol and its inventor check out http://www.interrobang-mks.com/

Grammar Girl (Mignon Fogarty) is a very interesting blogger who posts regularly (I pick her up from Facebook), and following on from my blog of 10 July 2015  - 'Those dreaded homophones', I would like to share this blog that she in fact also shared, which is by Neal Whitman. 

Have you ever had trouble remembering the difference between homoPHONES and homoNYMS? I have. And as if that’s not confusing enough, someone will bring up homoGRAPHS. I’m going to offer a simplified definition that will make sense to you if you’ll just agree with me on one point first: That thumbs are a kind of finger. You agree with me, right? Good!

Some etymology will help here. The root homo-, you may already realize, means “same.” It’s the same Greek root that we find in homogeneous and homosexual, but not Homo sapiens, by the way. That comes from a Latin root meaning “human.”

Homophones
First let’s tackle homophones. The root –phone means “sound,” as it does in telephone and phonics. So homophones are words that sound the same, such as doe a deer, a female deer, and dough that you bake into bread.

Homographs
Next, let’s do homographs. The root -graph means “write,” just as it does in autograph and telegraph. So homographs are words that are written the same—that is, words that have the same spelling. For example, there’s the verb tears, as in “Squiggly tears the speeding ticket in two,” and the noun tears, meaning the salty drops of water that ran down your cheek when you watched the movie Inside Out. They’re homographs because they’re both spelled T-E-A-R-S. 

Homonyms
Now we can bring in homonyms. The –onym root means “name.” You also hear it in anonymous, which literally means “without a name,” and of course, in the words synonym and antonym. Homonyms are words that have the same name; in other words, they sound the same and they’re spelled the same. For example, pen meaning the writing instrument, and pen meaning an enclosure for an animal, are homonyms. They have the same pronunciation, “pen,” and they’re both spelled P-E-N. To put it another way, homonyms are both homophones and homographs! You can even illustrate this with a cute little Venn diagram of two overlapping circles. One circle contains homophones; the other circle contains homographs; and the football in the middle contains homonyms.

So homophones sound the same; homographs are spelled the same; and homonyms do both. That’s all you need to know. 

At this point, if you already knew the difference between the three words, you might be saying, “Now hold on just one minute! Homographs are words that are spelled the same, and don’t sound the same! Homophones are words that sound the same, but aren’t spelled the same!”

This is where my fingers and thumbs analogy comes in. Sure, when somebody says, “Ow! I cut my finger!” you probably figure they cut their pointer, tall man, ring finger, or pinky. That’s because if they’d cut their thumb, they’d probably have been more specific and said, “Ow! I cut my thumb!” Even so, you agree that a thumb is a finger—a special finger, but still a finger. In the same way, it makes more sense to say that pen and pen are special homophones than to say they’re not homophones. And by the same reasoning, it’s simpler to think of pen and pen as special homographs than say they’re not homographs. 

Of course, if you really want to, you can write the definitions of homophone, homonym, and homograph so that there’s no overlap, but I suspect that definitions like that are part of the reason for people’s confusion.

That piece was by Neal Whitman who has a PhD in linguistics and blogs at literalminded.wordpress.com.
You can find Grammar Girl at quickanddirtytips.com