One of the questions that we get here is “what is font embedding, and why do I need it?”

That’s an excellent question!

To understand the how and why of embedded fonts, you need to understand a few basic computer concepts.

• Computers can only use and access computer files or programs that are on that computer. If your computer doesn’t have the Adobe Photoshop program, and your friend Sally sends you a Photoshop file, (not an image made with Photoshop, but the actual Photoshop file that she used to make it) you can’t open it and make changes in it.
• Fonts are actually small computer “programs” that tell text how to appear.
• If the person who receives your computer file (or eBook!) doesn’t have the font on his device, that you told your book to display, guess what? He won’t see that font. His computer or device will replace the font you told it to display, with what he actually has on his computer or eReading device.
• Fonts for your text are like clothing for your body. If you want to appear at an event in a red dress or a royal blue tuxedo, you have to have it to wear. No red dress, no wearing that red dress.  That simple. 

So, to understand this more easily, let’s suppose that Janey, is going on holiday to a fancy tropical paradise, with her hubby, Fred.  They don’t want to be like everybody else, all boring and stuff, going on planned tours. Not Fred and Janey.  They’re gonna bring it!

"Fonts for your text are like clothing for your body."

They plan to tear up the town! Eat, drink, be merry and dance the night away.  When thinking about her trip, Janey thinks about just how hot she’s going to look in that red dress.  Oooooh, baby!  Smokin’!

But, here’s the thing. For Janey to look hot in that dress while she’s in Turks and Caicos, she has to take the dress with her.  I know, you’re shaking your head, thinking, “duh, no kidding!”

If Janey forgets to pack it—if the dress isn’t in her suitcase or her hanging bag, just having it sitting at home, in her closet, won’t let her to wear it on her trip.  No dress in the suitcase means no dress to wear.

If you think, “Oh-Emm-Gee, I love this font,” and you want it to display in your eBook, then, the font needs to travel with your eBook. Think of it like the font travelling in an itty-bitty suitcase, with the eBook.  If the font travels with the eBook, then everybody who gets the book can see that font, while your text is wearing it. 

But, if the font is not in that itty-bitty suitcase, well…just like poor Janey and her red dress, your text can’t wear it.  If you didn’t pack its suitcase, it can only wear what’s already on the device.  Sadly, just like you don’t expect your resort to have a selection of perfectly-sized and styled clothing, in your closet, ready to go when you arrive, eReader devices don’t have a large selection of fonts for your eBook to use.  Most Kindles have kind of predictable and not-very-exciting closets; they have Times New Roman, Bookerly, Garamond, Courier, Helvetica or Arial and maybe one of the other sans-serif fonts, like Futura.

If your title page uses something different, like Brilon, let’s say—well, that can’t display.  No Brilon in the suitcase or closet, no Brilon on the text.  No exceptions.

So—if you want to wear the dress that you want to wear, not what’s available; if you want to use the font that you chose for your title page and your chapter heads, to distinguish your book from the others, then you have to embed fonts. 

For technological reasons, this can’t be done using Word to build an ebook at Kindle Direct Publishing (or other places). It can only be done when an eBook is coded, in HTML and built as an eBook, in an eBook format, like MOBI or ePUB.  For some fonts--for example, Avenir Next, it can be a very expensive proposition, because using those fonts may require special ($$$) licensing.  (For example, licensing the Avenir Next family for an eBook is thousands of dollars! Yes, for ONE use!)

So, that's what font embedding is--nothing more than clothes for your text to wear, when it's out and about.  Just remember--just like your dress, that font has to travel with your text, if your text wishes to wear it.