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Encoding Schemes: Translating Human To Machine

Understand how text is mapped to unique decimal codes and then to binary, using ASCII, ISCII, and UNICODE.

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The Secret Cipher of Keys

Hook explaining that keys map to numbers.

Your computer keyboard doesn't actually send letters to the computer. When you press 'A', it internally sends the number 65! This is called encoding: the mechanism of converting data into an equivalent cipher using a specific code.
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ASCII: The Original Standard

Explanation of ASCII, 7-bit system, and key values.

In the early 1960s, computers couldn't easily communicate because they represented keyboard keys in different ways. The solution was ASCII (American Standard Code for Information Interchange).

It became the universal language for basic character representation on digital systems.

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Encoding the word DATA

Visual showing the word DATA converting to ASCII then binary.

Polished process flowchart, rounded card-style nodes, pastel gradient fills, elegant sans-serif typography, generous whitespace, subtle connecting arrows, light neutral background. Visual showing the word 'DATA' being encoded step-by-step: 'D' maps to 68 then to 1000100, 'A' maps to 65 then to 1000001, 'T' maps to 84 then to 1010100, 'A' maps to 65 then to 1000001. Letters transform into decimal codes, then into 7-bit binary blocks.
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Each letter is mapped to an ASCII decimal code, which is then translated into a 7-bit binary format the computer can process.

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Test Your ASCII Knowledge

Fill in the blanks for ASCII concepts.

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The encoding schemewas developed in the early 1960s to standardise character representation and is still the most commonly used coding scheme. It initially usedbits to represent characters, meaning it could encode a total of 128 different characters on the English keyboard. When a key is pressed, it is internally mapped to a unique decimal value; for example, the decimal value for the capital letter 'A' is. Because this original scheme only encoded English characters, an 8-bit standard calledwas developed in the mid-1980s for Indian language character sets. Eventually, a universal standard calledwas developed to incorporate all the characters of every written language in the world. The overall mechanism of converting data into an equivalent cipher using a specific code is called, which is essential for digital systems to process textual data into binary numbers.
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Going Global: ISCII and UNICODE

Explanation of ISCII for Indian scripts and UNICODE for universal coverage.

Beyond English: ISCII

While ASCII was revolutionary, it had a major limitation: it only encoded the English character set.

To facilitate the use of Indian languages on computers, ISCII (Indian Script Code for Information Interchange) was developed in the mid-1980s.

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Comparing Encoding Schemes

Visual comparison of ASCII, ISCII, and UNICODE capacity.

Clean side-by-side comparison, consistent visual treatment for both sides, same scale and style, pastel color coding to distinguish categories, elegant typography, white background, generous whitespace. Visual showing three levels of encoding: ASCII (7-bit, 128 chars, English only), ISCII (8-bit, 256 chars, Indian scripts + English), and UNICODE (Variable bits, millions of chars, all world languages). A nested diagram or funnel indicates that UNICODE contains ISCII, and ISCII contains ASCII.
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Encoding schemes evolved from 7-bit English-only ASCII to the universal UNICODE standard, which encompasses all world languages.

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Which Standard?

Multiple choice question differentiating the standards.

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An international software team is upgrading a legacy messaging system to support global users. Which of the following statements about their encoding options is TRUE?