Ascii text

ASCII abbreviated from American Standard Code For Information Interchange, is a standard for character encoding in computer systems. Name of this standard is recognisable and used for long time, however IANA organisation strongly suggest to use US-ASCII name, to emphasise origins of standard and languages supported. Currently it is widely used and recognised as the most popular mechanism used for character encoding. ASCII contains a set of 128 characters which includes letters, digits, symbols and control sequences. ASCII is a United States version of the International Standard for Information Processing. This character encoding system uses 7-bit character sets. Main goal of ASCII is to interchange information among data processing systems, computers and every equipment associated with such machines .

Mechanism

ASCII works in similar way as other character encoding systems (e.q. MCS - Multinational Character Set). Standard assumes that each character has a binary code assigned, which is representing the position of character in an arbitrarily ordered set of characters (ASCII table). For example, letter F has decimal code 70 which in binary equals to 1000110 whereas number 6 has decimal representation and position in table equal to 54 which in binary can be represented as: 110110. Numeric representation of letter is convenient for computer systems as they operate on numbers. ASCII provides good solution for comparing letters and words as they can be compared using mathematical operators like: greater than, less than or equals.

ASCII set

ASCII set contains many different symbols and characters. First elements of ASCII table are Control Characters which can be divided in 6 groups:

• Transmission Control Characters - used for controlling the transmission between devices,
• Format Effectors - intended to control the layout, formatting and positioning of text especially for displays or printers,
• Code Extension Control Characters - used for extending the character set of code,
• Device Control Characters - intended to control devices connected to main system,
• Information Separators - used to separate and divide data in to logical groups,
• Other Control Characters - used to control characters and situations that are not suited to any other group.

Control characters have decimal representation in numbers 0-32. However, there is also one more character used for deleting other symbols and it is called DEL and is positioned at the end of table with number 127. Values between 32 and 127 are representing other characters that can be used by user to create text. Special characters like question mark, quotes, exclamation point are first in the order and are represented by values from 33 to 64 with exception of values 48-57 which stand for numbers 0-9. Upper case letters are represented by values 65-90. Then ASCII table contains few other special characters like brackets. Lower case letters are represented by range 97-122. ASCII table ends with braces, vertical line, tilde and mentioned before DEL special character.

ASCII art

As ASCII consists of characters it can be used to assemble words, sentences but also other representations of thought. Using proper algorithms and mechanism it is possible to construct images using letters arranged in certain way. ASCII art can be divided into two groups. Tone-based art which main goal is to achieve the graphic by density of glyph. Other group, structure-based art uses the line of glyph to represent graphics and especially its outlines and borders. Structure based art is using smaller amounts of ASCII characters as it is not filling the insides of objects. ASCII art can be created manually and using software programs that generate graphics automatically.

Examples of Ascii text

• Plain text emails: Plain text emails are emails that are composed of plain ASCII characters, without any special formatting or styling.
• Text-based webpages: Text-based webpages are webpages that are composed solely of plain ASCII characters, with no special formatting or styling.
• Command-line programs: Command-line programs are programs that are run from the command line, using only ASCII characters for input and output.
• Programming source code: Programming source code is code written for a computer program, using only ASCII characters for the syntax and structure.
• Configuration files: Configuration files are text-based files that are used to configure a program or system, using only ASCII characters.

Advantages of Ascii text

ASCII text has many advantages. Below is a list of the most important ones:

• ASCII is the most widely-used character encoding in the world, making it the best choice for data interchange between different systems. It is well-supported by almost all computer systems and programs, making it easy to use.
• ASCII is a very simple character encoding standard, with only 128 possible characters, making it easy to learn and use.
• ASCII is a 7-bit encoding, which means that it takes up less storage space than other character encodings, making it the most efficient option for storing and transferring data.
• ASCII is a standard format, meaning that it can be read and understood by people, machines, and programs. This allows for easier data interchange between different systems, and makes it easier to debug problems in programs.

Limitations of Ascii text

American Standard Code for Information Interchange (ASCII) is a character encoding standard used in computer systems. While it is widely used, it has some limitations. The following are some of the main limitations of ASCII text:

• ASCII is limited to 8 bits, which allows a maximum of 256 characters. This limits the use of special characters, accents and symbols, making it difficult to type in languages other than English.
• ASCII does not support text formatting, meaning that text color, font size, spacing, and other formatting features cannot be applied.
• ASCII does not support binary data, meaning that files such as images, audio, and video cannot be stored in ASCII format.
• ASCII also has limited compatibility with other character encoding standards, so it is not always suitable for data exchange.

Other approaches related to Ascii text

One of the approaches related to ASCII text is the use of other encoding schemes. The following are the other approaches:

• Unicode - Unicode is a character encoding standard that supports a wide range of languages and symbols. It is a superset of ASCII and is used in many applications and websites.
• Binary - Binary is a type of encoding scheme that uses ones and zeroes to represent data. It is commonly used to store large amounts of data in a compact form.
• HTML - HTML (HyperText Markup Language) is a web-based language used to create and structure webpages. It uses ASCII characters, as well as special characters, to define the structure and content of the page.

These approaches are all related to ASCII text in the sense that they are used to represent and store data. Each approach has its own unique features and is often used for different tasks. In conclusion, ASCII is an important encoding standard, and there are many other approaches that are related to it.

Footnotes

Ascii text — recommended articles

Balanced design — Knowledge map — Support vector machine — Database — Decision tree — Box diagram — Algorithm — Types of information — Mollier chart

References

• ANSI, X. (1986). 4: Coded Character Set—7-Bit American National Standard Code for Information Interchange, Am. Nat’l Standards Inst., New York. ISO 690.
• Beebe, N. (1990). Character set encoding, TUGboat, 11(2), 171-175. ISO 690.
• Character Sets, (ang.), iana.org.
• Fischer, E. (2002). The evolution of character codes, 1874-1968. citeseerx. ist.
• Fisher, E. G., & Gilbert, P. D. (1993), U.S. Patent No. 5,225,833, Washington, DC: U.S. Patent and Trademark Office.
• Miyake, K., Johan, H., & Nishita, T. (2011), An interactive system for structure-based ASCII art creation., Proc. NICOGRAPH Int., 4-3.
• Shinge, S. R., & Patil, R. (2014). An encryption algorithm based on ASCII value of data. International Journal of Computer Science and Information Technologies, 5(6), 7232-7234.
• Weiman D., (2012), Decimal - Binary - Octal - Hex - ASCII Conversion Chart.
• Xu, X., Zhang, L., & Wong, T. T. (2010), Structure-based ASCII art. ACM Transactions on Graphics (TOG), 29(4), 52. ISO 690.

Author: Michał Bałos