There are several distinct aspects to character storage and display by computer software:
Each piece of software works with a character set. A character set is a set of symbols, including letters, digits, spaces and other symbols.
To handle these characters, each piece of software employs a character set encoding, in which each character is mapped onto one or more bytes of information, typically represented as hexadecimal numbers. This encoding is also called a code page.
Database servers, which sort characters (for example, list names alphabetically), use a collation. A collation is a combination of a character encoding (a map between characters and hexadecimal numbers) and a sort order for the characters. There may be more than one sort order for each character set; for example, a case-sensitive order and a case-insensitive order, or two languages may sort characters in a different order.
Characters are printed or displayed on a screen using a font, which is a mapping between characters in the character set and their appearance. Fonts are handled by the operating system.
Operating systems also use a keyboard mapping to map keys or key combinations on the keyboard to characters in the character set.