Extended ASCII, an 8-bit evolution of the original 7-bit ASCII standard, supports international text by expanding the character s…

Question

Extended ASCII, an 8-bit evolution of the original 7-bit ASCII standard, supports international text by expanding the character set. How many total codes does it provide?

1. A. 512 codes for voice recordings
2. B. 1024 codes for video compression
3. C. 128 codes limited to English letters
4. D. 256 codes including accented characters (Correct answer)

Correct Answer

Option D — 256 codes including accented characters

Detailed Solution & Explanation

The correct answer is 256 codes including accented characters.

Key Points

• The arithmetic settles it: 8 bits give $2^8 = 256$ distinct codes. Extended ASCII therefore provides 256 characters, numbered 0 to 255.
• Original ASCII was 7-bit, giving $2^7 = 128$ codes — enough for English letters, digits, punctuation and control characters, but nothing more.
• The extra eighth bit doubles the set, and the additional 128 codes carry accented letters (é, ñ, ü), currency symbols and box-drawing characters for European languages.
• The rejected options attach the wrong count to the wrong purpose — 512 and 1024 are not powers reachable with 8 bits, and 128 describes the *original* standard, not the extended one.

Additional Information

• The general rule is that $n$ bits encode $2^n$ values: 4 bits → 16, 8 bits → 256, 16 bits → 65,536. This single relation answers most questions of this type.
• ASCII stands for *American Standard Code for Information Interchange*. Useful reference values: `A` = 65, `a` = 97, `0` = 48 — note lowercase is exactly 32 above uppercase.
• Extended ASCII was superseded by Unicode, which accommodates over a million code points and covers virtually every writing system; UTF-8 encodes it while remaining backward-compatible with the original 7-bit ASCII.
• 1 byte = 8 bits, which is why "extended ASCII" and "one character per byte" describe the same thing.