Character Encoding

Question

My text editor allows me to code in several different character formats Ansi, UTF-8, UTF-8(No BOM), UTF-16LE, and UTF-16BE.

What is the difference between them?

What is commonly regarded as the best format (I'm using Python if that makes a diffrence)?

Answer 1

Here. Note that "ANSI" is usually CP1252.

Answer 2

You'll probably get greatest utility with UTF-8 No BOM. Forget that ANSI and ASCII exist, they are deprecated dinosaurs.

Answer 3

• "Ansi" is a misnomer and usually refers to some 8-bit encoding that's the default on the current platform (on "western" Windows installations that's usually Windows-1252). It only supports a small set of characters (256 different characters at most).
• UTF-8 is a variable-length, ASCII-compatible encoding capable of storing any and all Unicode characters. It's a pretty good choice for western text that should support all Unicode characters and a very viable choice in the general case.
• "UTF-8 (no BOM)" is the name Windows gives to using UTF-8 without writing a Byte Order Marker. Since a BOM is not needed for UTF-8, it shouldn't be used and this would be the correct choice (pretty much everyone else calls this version simply "UTF-8"!).
• UTF-16LE and UTF-16BE are the Little Endian and Big Endian versions of the UTF-16 encoding. As UTF-8, UTF-16 is capable of representing any Unicode character, however it is not ASCII-compatible.

Generally speaking UTF-8 is a great overall choice and has wide compatibility (just make sure not to write the BOM, because that's what most other software expects).

UTF-16 could take less space if the majority of your text is composed of non-ASCII characters (i.e. doesn't use the basic latin alphabet).

"Ansi" should only be used when you have a specific need to interact with a legacy application that doesn't support Unicode.

An important thing about any encoding is that they are meta-data that need to be communicated in addition to the data. This means that you must know the encoding of some byte stream to interpret it as a text correctly. So you should either use formats that document the actual encoding used (XML is a prime example here) or standardize on a single encoding in a given context and use only that.

For example, if you start a software project, then you can specify that all your source code is in a given encoding (again: I suggest UTF-8) and stick with that.

For Python files specifically, there's a way to specify the encoding of your source files.