ASCII control character
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Definition
Noun: A character from the ASCII (American Standard Code for Information Interchange) character set that is used for device control or formatting, rather than for representing a written symbol. These characters are typically non-printing and are invoked by pressing the Control key in combination with another key.
Usage
ASCII control characters are used to send commands to output devices like printers, terminals, or communication systems. They control functions such as moving the cursor, starting a new line, or signaling the end of a transmission.
Examples
- In a text file, an ASCII control character like (Line Feed, code 10) tells the computer to move to the next line.
- The (Delete, code 127) character is an ASCII control character used to erase the preceding character.
- Early computer terminals used the (Bell, code 7) control character to sound an audible alert.
Advanced Usage
- In Data Transmission: Control characters like (Start of Text) and (End of Text) are used to frame data in communication protocols.
- Escape Sequences: The (Escape, code 27) character is often used as the first part of a longer command sequence for terminals and printers.
Variants and Related Words
- Control Character: A more general term for any non-printing character used for control purposes, not limited to the ASCII standard.
- Non-Printing Character: Any character that does not represent a written symbol (e.g., a space, tab, or control character).
Synonyms
- Control code
- Non-printing character (in a specific technical context)
Related Phrases
- Ctrl Key Combination: The method of generating these characters, e.g., pressing generates the (bell) character.
- Caret Notation: A common way to represent control characters in text, where the character is shown as a caret () followed by a letter (e.g., represents Carriage Return).
Noun
- ASCII characters to indicate carriage return or tab or backspace; typed by depressing a key and the control key at the same time