An Indezine reader, whom I met in person described the PowerPoint double-byte font scare as a poisonous king cobra snake! Although this sounds like an exaggeration, this thought has lingered with me for many years. Let’s take this dramatic approach further. Sooner or later, you will see PowerPoint look at you like a cobra that’s showing its fangs, and is ready to bite. You want to make sure you are not bitten, and wouldn’t it be nice if the cobra quietly goes back to its hole and rests there in peace and leaves you alone?
Yes, there’s some play happening here between the words ‘byte’ and ‘bite’!
So what exactly is the single and double-byte fonts problem? To understand this problem, we need to understand what they mean. Even before we get there, we need to understand what a Unicode font is, so do visit this page about Unicode fonts before you read further.
All non-Unicode fonts, also known as fonts with ASCII encoding, can be divided into two types:
1. Single-byte fonts
Single-byte fonts are the ones we use often, because most fonts are of this type. Single-byte fonts cannot exceed 256 characters. Yes, you may have guessed it—each alphabet, number, or other character counts as one of these 256 characters. Most of these fonts not only encompass all English characters but also some characters from other Latin scripts, Central European, Cyrillic, Turkish, Greek, Thai, Arabic, and Hebrew characters.
2. Double-byte fonts
Double-byte fonts are used when the 256 character limit is not enough. Technically, double-byte fonts are just multi-byte fonts. Double-byte fonts use 256 characters, multiplied by 256, and thus can possess 65,536 characters. Of course, you could similarly have triple-byte fonts with 256x256x256 characters, but in the real world, multi-byte fonts are double-byte fonts.
But why do we need multi-byte fonts? Are 256 characters not enough? Yes, they are not enough, because when you add support for Far Asian languages such as Japanese, Korean, and Chinese, the 256 character limit is a roadblock. Fortunately, double-byte fonts can hold many more characters. Some double-byte fonts that may be installed on Windows systems are DengXian, FangSong, Microsoft YaHei, and SimSun, as shown in Figure 1, below which shows the PowerPoint fonts drop-down list within the Replace Font dialog.
See Also: List of Double-byte Fonts
Figure 1: Double-byte fonts in Replace Fonts
If these names sound Far East Asian, that’s because these fonts belong to scripts such as Japanese, Chinese, and Korean.
OK, now that you know how these two font types differ, what is the big issue?
First, if you use a double-byte font for a PowerPoint presentation that uses only English characters, you are using a font that is larger in size. Double-byte fonts can be much larger in size than single-byte fonts, and your presentation may not run as smoothly as it would with single-byte fonts. Of course, this is no longer a big issue in today’s better-equipped computer systems.
The larger problem comes up when you try to use a single-byte font instead of a double-byte font. Yes, you can find every text box, placeholder, or shape that uses a double-byte font and replace it with a single-byte font manually. But you cannot do so for an entire presentation at one go, using PowerPoint’s Replace Fonts option. And this is when we need to use cobra analogy!
In future posts, we will look at ways to tackle this problem. We will also update this post and link to newer posts as they are released.