In computer and machine-based telecommunications terminology, a character is a unit of information that roughly corresponds to a grapheme, grapheme-like unit, or symbol, such as in an alphabet or syllabary in the written form of a natural language. Examples of characters include letters, numerical digits, common punctuation marks (such as "." or "-"), and whitespace. The concept also includes control characters, which do not correspond to visible symbols but rather to instructions to format or process the text. Examples of control characters include carriage return and tab as well as other instructions to printers or other devices that display or otherwise process text. Characters are typically combined into strings. Historically, the term character was used to denote a specific number of contiguous bits. While a character is most commonly assumed to refer to 8 bits (one byte) today, other options like the 6-bit character code were once popular, and the 5-bit Baudot code has been used in the past as well. The term has even been applied to 4 bits with only 16 possible values. All modern systems use a varying-size sequence of these fixed-sized pieces, for instance UTF-8 uses a varying number of 8-bit code units to define a "code point" and Unicode uses varying number of those to define a "character". Encoding Computers and communication equipment represent characters using a character encoding that assigns each character to something an integer quantity represented by a sequence of digits, typically that can be stored or transmitted through a network. Two examples of usual encodings are ASCII and the UTF-8 encoding for Unicode. While most character encodings map characters to numbers and/or bit sequences, Morse code instead represents characters using a series of electrical impulses of varying length. Terminology Historically, the term character has been widely used by industry professionals to refer to an encoded character, often as defined by the programming language or API. Likewise, character set has been widely used to refer to a specific repertoire of characters that have been mapped to specific bit sequences or numerical codes. The term glyph is used to describe a particular visual appearance of a character. Many computer fonts consist of glyphs that are indexed by the numerical code of the corresponding character. With the advent and widespread acceptance of Unicode and bit-agnostic coded character sets, a character is increasingly being seen as a unit of information, independent of any particular visual