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Information coding systems common mistakes
Study Information coding systems with curriculum-aligned Common Mistakes resources, practice links, and exam-focused support.
At a glance
common mistakes
Resource type
Topic
Information coding systems
Common mistakes
Assuming a digit character is the same as its value
Treating the character code for '7' as if it were the pure binary value seven.
Fix itIdentify whether the data is text or a number. A character code for '7' represents the character; the numerical value 7 has its own pure binary representation.
Confusing ASCII's bit length with Unicode
Claiming that all Unicode characters use exactly 7 bits, or that standard ASCII can represent every character used in every language.
Fix itState that standard ASCII uses 7 bits and has a limited character set. Unicode was introduced to support a much wider range of characters.
Confusing a checksum with a check digit
Describing a checksum as an extra digit added to an identifier, or describing a check digit as a value calculated from a whole block of data.
Fix itA checksum is calculated from a block of data, while a check digit is an additional digit calculated from the other digits in a number or identifier.
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