What is the difference between ASCII and Unicode encoding?

What is the difference between ASCII and Unicode encoding?

• A. ASCII encodes 128–256 characters using 7/8 bits; Unicode uses UTF-8/UTF-16.
• B. ASCII can encode all characters.
• C. Unicode uses fixed 16-bit encoding only.
• D. ASCII is a Unicode encoding.

Answer: (A)

ASCII is a simple encoding that covers basic characters and control codes using 7 bits, giving 128 distinct values. Some systems use an 8th bit to create an extended ASCII set up to 256, but those extensions aren’t standardized the same everywhere. Unicode, by contrast, is a universal character set designed to represent characters from virtually all languages, with code points far beyond 128. To store Unicode text, we use encodings like UTF-8 or UTF-16, which map those code points to bytes. UTF-8 is variable-length and compatible with ASCII for the first 128 code points, while UTF-16 uses 16-bit units and can require more bytes per character. In short, ASCII handles a small, fixed set of characters, while Unicode provides a vast range of characters and flexible ways to encode them as bytes.

ASCII is a simple encoding that covers basic characters and control codes using 7 bits, giving 128 distinct values. Some systems use an 8th bit to create an extended ASCII set up to 256, but those extensions aren’t standardized the same everywhere. Unicode, by contrast, is a universal character set designed to represent characters from virtually all languages, with code points far beyond 128. To store Unicode text, we use encodings like UTF-8 or UTF-16, which map those code points to bytes. UTF-8 is variable-length and compatible with ASCII for the first 128 code points, while UTF-16 uses 16-bit units and can require more bytes per character. In short, ASCII handles a small, fixed set of characters, while Unicode provides a vast range of characters and flexible ways to encode them as bytes.