What is the difference between UTF-8 and Unicode?

Question

I have heard conflicting opinions from people - according to the Wikipedia UTF-8 page.

They are the same thing, aren\'t they? Can someone clarify?

Answer 1

They are the same thing, aren't they?

No, they aren't.

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I think the first sentence of the Wikipedia page you referenced gives a nice, brief summary:

UTF-8 is a variable width character encoding capable of encoding all 1,112,064 valid code points in Unicode using one to four 8-bit bytes.

To elaborate:

• Unicode is a standard, which defines a map from characters to numbers, the so-called code points, (like in the example below). For the full mapping, you can have a look here.

  ! -> U+0021 (21),  
  " -> U+0022 (22),  
  \# -> U+0023 (23)
  

• UTF-8 is one of the ways to encode these code points in a form a computer can understand, aka bits. In other words, it's a way/algorithm to convert each of those code points to a sequence of bits or convert a sequence of bits to the equivalent code points. Note that there are a lot of alternative encodings for Unicode.

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Joel gives a really nice explanation and an overview of the history here.