NIMCET 2008 — Computer PYQ

To answer this accurately, we must distinguish between the original standard and how it is implemented in modern computing.

1. The Original Standard (7-bit ASCII)

The ASCII (American Standard Code for Information Interchange) was originally designed as a 7-bit code.

• With 7 bits, the number of unique characters that can be represented is $2^7=128$.

• These 128 characters include control characters (like "Line Feed"), uppercase and lowercase letters, numbers, and basic punctuation.

2. Modern Storage (8-bit implementation)

In practical computer storage and data transmission:

• Computers usually store data in bytes, where $1\text{ byte}=8\text{ bits}$.

• When a 7-bit ASCII character is stored in an 8-bit byte, the 8th bit (the most significant bit) is typically set to 0 or used as a parity bit for error checking.

• Extended ASCII uses all 8 bits to represent $2^8=256$ characters, adding special symbols and non-English characters.

3. Choosing the Correct Answer

In the context of competitive exams and the fundamental definition of the standard:

• If the question asks for the number of bits defined by the ASCII standard, the answer is 7.

• If the question refers to how much space it takes in a standard memory byte, the answer would be 8.

However, by definition, "Standard ASCII" is a 7-bit character set.

Final Answer:

The correct option is (a) 7.