Data Encoding

Data encoding in computer science is the process by which data is converted into a form that allows it to be properly used by different systems. It includes transforming information from one format or code to another.

The two common aspects of data encoding in computer science are transforming data into binary code and encoding for data transmission to ensure smooth transference over networks.

The three primary data encoding methods are character encoding, numeric encoding and Boolean encoding.

Character encoding converts characters into a format that can be utilized by computer systems. The most prevalent types are ASCII and Unicode.

Data encoding is crucial in encryption, transforming data into an unreadable format to secure it. Only users who possess the correct decryption key can read the data.

Encoding data simplifies, streamlines, and standardizes the process of transmitting data between systems or over networks, reducing the possibility of data misinterpretation.

Encoding methods like Huffman coding allow efficient binary representations for data storage and communication, thereby reducing required bandwidth or memory space.

Data encoding forms an integral part of encryption techniques used to disguise data, making it unreadable to anyone who doesn't possess the correct decryption key.

Encoding techniques facilitate data compression reducing the amount of storage required and enhances retrieval of information.

Encoding helps in maintaining data integrity by foreseeing and handling transmission errors through redundancy and error detection and correction mechanisms.

Data encoding in Internet-based communication systems changes the content of a message into a format that's easily transferrable over the Internet. For instance, MIME standard supports different types of data and converts them into a standard text format for easy sending and correct decoding.

Email attachments, like images or documents, are encoded in Base64, making them readable in non-binary data environments. On the internet, URL encoding is used to replace unallowable characters within a URL, maintaining the integrity of the address.

In music and video streaming services, data encoding is used to compress a song or a movie to use as little data as possible, while still maintaining the high-quality standard.

SHA encoding is used in data encryption, transforming data into a unique cryptographic hash, which doesn't allow decryption. This method is used notably for password storage; instead of storing the actual password, the system stores the SHA-encoded hash.

In computing, character encoding is used in different software systems or applications, like UTF-8 encoding for the internet and Unix-based systems. It enables communication and data representation across platforms and languages effectively. A commonly seen example is QR codes.

Unicode is a universal character encoding system that provides a unique identifier for every character, regardless of the platform, device, application, or language and can represent characters from almost every written language.

The benefits of Unicode include universality (a single encoding scheme for almost every character), consistency (characters appear the same across different platforms and devices), and efficiency (reduces complexity of encoding conversions).

Before Unicode, multiple character encoding schemes led to conflicts and inconsistencies. Unicode established a consistent and interoperable text encoding system, enabling accurate global communication.

Each encoding form assigns a unique sequence of bytes, or code units, to each Unicode character. The difference is in the size and number of code units required: UTF-8 uses 8-bit code units, UTF-16 uses 16-bit code units, and UTF-32 uses 32-bit code units.

The UTF-8 format is advantageous due to its backward compatibility with ASCII, ensuring seamless integration with existing ASCII-based systems. It also uses 1-4 bytes per character, maintaining efficient memory usage.

The Byte Order Mark (BOM) is a Unicode character used to signal the endianness (byte order) of a text file or stream. Its code point is U+FEFF.

The four forms of Unicode Normalisation are NFC, NFD, NFKC, and NFKD. They translate Unicode characters into standard forms for data consistency. NFC merges characters, NFD decomposes characters, and NFKC and NFKD involve 'compatibility characters'.

Unicode Collation is the arrangement of text strings based on language-specific rules. It determines the correct order for sorting different Unicode characters extending beyond basic alphabetic sequence.

The processes involved in handling and processing Unicode data include Unicode Normalisation, Unicode Collation, String Prepping, and Converting between different encodings.

Each Unicode character maps to a specific sequence of bytes, called code units. The encoding mode (UTF-8, UTF-16, or UTF-32) determines the number of bytes for each character.

Byte order or endianness defines the order in which a sequence of bytes is stored. Two forms exist: big-endian, where the most significant byte is stored first, and little-endian, where the least significant byte goes first.

Benefits are universality, consistency, and compatibility, especially with ASCII. Limitations include high space usage for inclusive encoding forms like UTF-32, complexity in processing Unicode due to variable-length encoding, and handling complexity due to multiple forms of encoding and nuances like normalisation.

Unicode compression techniques aim to reduce the size of Unicode data, improving storage, transmission, and processing efficiency. They exploit redundancies or patterns in data to reduce the number of bytes used to represent specific characters.

The three main benefits of Unicode compression are efficient storage (saving space), speedy transmission (faster data exchange over networks), and quicker processing (enhanced performance of operations like sorting and searching).

Some popular methods include Huffman coding, Burrows-Wheeler Transform, Standard Compression Scheme for Unicode (SCSU), and Binary Ordered Compression for Unicode (BOCU).

ASCII stands for American Standard Code for Information Interchange.

ASCII includes 128 characters: 32 control codes, 95 printable characters, and a DEL character.

ASCII code provides a way to standardise text, allowing computers from different manufacturers or with different software to exchange and read information seamlessly.

In ASCII, 'COMPUTER' is interpreted as "67, 79, 77, 80, 85, 84, 69, 82".

ASCII characters are the building blocks used to standardise text in computers, making them indispensable to modern computer operations.

The ASCII table is split into two parts - the first part (0-31) is for non-printable control characters, and the second part (32-127) is for printable characters including letters, numerals, and punctuation.

The printable section of the ASCII table (values 32-127) contains letters, numerals, punctuation, and certain special characters.

Frequent ASCII characters include the space character (32), uppercase and lowercase English letters (65-90, 97-122), newline character ('\n', 10), carriage return character ('\r', 13), and common punctuation marks.

The ASCII encoding process converts each character, symbol, digit or control key entered on a keyboard into a 7-bit binary number. This number is used by computer programs to perform appropriate actions.

The sequence includes capturing the input from a key press which sends a unique ASCII value, this value is processed by the computer's basic I/O system, then it could be stored or manipulated by programs.

Each character typed has a unique ASCII value which is sent to the computer. For example, 'H' is 72, 'e' is 101, 'l' is 108, 'o' is 111, and '\n' is 10 in ASCII.

Understanding the ASCII encoding process is essential when dealing with text data in programming. It provides a simple and efficient way of encoding characters and non-printable control commands.

ASCII supports 128 standard characters.

It's not compatible with languages and cultures that don't differentiate between uppercase and lowercase letters.

ASCII lacks the capability to natively represent mathematical symbols beyond basic arithmetic operators.

Different techniques and encoding standards, like UTF-8 and UTF-16, have been created to accommodate these characters.