What is the ANSI Charset?

The ANSI charset is the default multibyte charset for a given computer. The ANSI charset (or code page) depends on the locale of the computer. For German computers it might be Window-1252, for Japanese computers it may be Shift_JIS

What is a MultiByte Charset?

Generally, all charsets except Unicode (2-bytes/char, also known as utf-16) are called "multibyte". This includes us-ascii. Some multibyte charsets represent characters in a single byte, others represent characters in variable lengths of bytes. One example is utf-8, which is the multibyte encoding for Unicode. (Google's search result pages use utf-8.)

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