Unicode and ASCII are both character encoding standards used in computing to represent text. They share some similarities, which are important to understand in the context of text encoding and processing.

Common Ground

• Character Encoding: Both Unicode and ASCII are methods for encoding text characters into binary numbers that computers can understand. They provide a way to represent characters from the keyboard in a format that can be stored and processed by computers.

• ASCII Compatibility: Unicode is designed to be fully compatible with ASCII. The first 128 characters of Unicode are identical to ASCII, which means that any ASCII text is also valid Unicode text. This was an intentional design choice to ensure backward compatibility with the pre-existing ASCII standard.

Code Points and Characters

• Code Points: Both standards use code points to define characters. In ASCII, there are 128 standard code points ranging from 0 to 127. Unicode extends this range significantly to accommodate a vast array of characters from different languages and scripts.

• Character Representation: In both ASCII and Unicode, characters like letters, numbers, and common punctuation marks are represented by specific code points. For example, in both ASCII and Unicode, the capital letter 'A' is represented by the code point 65.

Usage in Computing

• Widespread Use: ASCII was widely used in the early days of computing and set the foundation for text encoding. Unicode has since become the dominant standard due to its ability to represent a much larger set of characters, but it still respects the ASCII standard by including all ASCII characters within its encoding.