A character set is the key component behind displaying, manipulating and editing text, numbers and symbols on a computer. A character set is created through a process known as encoding i.e. each character is assigned with a unique code or value.
Unicode is a character set.
UTF-8 is encoding.
Unicode is a list of characters with unique decimal numbers (code points). A = 65
The Unicode Standard covers (almost) all the characters, punctuations, and symbols in the world.
Encoding is how these numbers are translated into binary numbers to be stored in a computer.
The Unicode Transformation Format (UTF) standard format made by Unicode consortium provides a unique number for any character.
UTF-8 can represent any character in the Unicode standard.
UTF-8 is backwards compatible with ASCII.
UTF-8 is the preferred encoding for e-mail and web pages.