Does HTML support multiple sequential blank spaces?
"Dot space" redirects here. For the animated film, see Dot in Space. Show
"␣" redirects here. Not to be confused with ⌴. In computer programming, whitespace is any character or series of characters that represent horizontal or vertical space in typography. When rendered, a whitespace character does not correspond to a visible mark, but typically does occupy an area on a page. For example, the common whitespace symbol U+0020 SPACE (also ASCII 32) represents a blank space punctuation character in text, used as a word divider in Western scripts. Overview[edit]Relative widths of various spaces in Unicode With many keyboard layouts, a whitespace character may be entered by pressing spacebar. Horizontal whitespace may also be entered on many keyboards with the Tab ↹ key, although the length of the space may vary. Vertical whitespace may be input by typing ↵ Enter, which creates a 'newline' code sequence in most programs. On older keyboards, this key may instead be labeled Return, a holdover from typewriter keyboards' carriage return keys, which generated an electromechanical return to the left stop (Unicode character U+000D) and a move to the next line (U+000A). Many early computer games used whitespace characters to draw a screen (e.g. Kingdom of Kroz), and word processing software used them to produce printed effects such as bold, underline, and strikethrough.[citation needed] The term "whitespace" is based on the appearance of the characters on ordinary paper. However, within an application, whitespace characters can be processed in the same way as any other character code and different programs may define their own semantics for the characters. Unicode[edit]The table below lists the twenty-five characters defined as whitespace ("WSpace=Y", "WS") characters in the Unicode Character Database.[1] Seventeen use a definition of whitespace consistent with the algorithm for bidirectional writing ("Bidirectional Character Type=WS") and are known as "Bidi-WS" characters. The remaining characters may also be used, but are not of this "Bidi" type. Note: Depending on the browser and fonts used to view the following table, not all spaces may be displayed properly.
Substitute images[edit]Unicode also provides some visible characters that can be used to represent various whitespace characters, in contexts where a visible symbol must be displayed: Unicode space-illustrating characters (visible)
Non-space blanks[edit]
Whitespace and digital typography[edit]On-screen display[edit]Text editors, word processors, and desktop publishing software differ in how they represent whitespace on the screen, and how they represent spaces at the ends of lines longer than the screen or column width. In some cases, spaces are shown simply as blank space; in other cases they may be represented by an interpunct or other symbols. Many different characters (described below) could be used to produce spaces, and non-character functions (such as margins and tab settings) can also affect whitespace. Variable-width general-purpose space[edit]In computer character encodings, there is a normal general-purpose space (Unicode character U+0020) whose width will vary according to the design of the typeface. Typical values range from 1/5 em to 1/3 em (in digital typography an em is equal to the nominal size of the font, so for a 10-point font the space will probably be between 2 and 3.3 points). Sophisticated fonts may have differently sized spaces for bold, italic, and small-caps faces, and often compositors will manually adjust the width of the space depending on the size and prominence of the text. In addition to this general-purpose space, it is possible to encode a space of a specific width. See the table below for a complete list. Hair spaces around dashes[edit]Em dashes used as parenthetical dividers, and en dashes when used as word joiners, are usually set continuous with the text.[27] However, such a dash can optionally be surrounded with a hair space,
U+200A, or thin space, U+2009. The hair space can be written in HTML by using the numeric character references
Computing applications[edit]Programming languages[edit]In programming language syntax, spaces are frequently used to explicitly separate tokens. In most languages multiple whitespace characters are treated the same as a single whitespace character (outside of quoted strings); such languages are called free-form. In a few languages, including Haskell, occam, ABC, and Python, whitespace and indentation are used for syntactical purposes. In the satirical language called Whitespace, whitespace characters are the only valid characters for programming, while any other characters are ignored. Excessive use of whitespace, especially trailing whitespace at the end of lines, is considered a nuisance. However correct use of whitespace can make the code easier to read and help group related logic. Most languages only recognize ASCII characters as whitespace, or in some cases Unicode newlines as well, but not most of the characters listed above. The C language defines whitespace characters to be "space, horizontal tab, new-line, vertical tab, and form-feed".[28] The HTTP network protocol requires different types of whitespace to be used in different parts of the protocol, such as: only the space character in the status line, CRLF at the end of a line, and "linear whitespace" in header values.[29] Command line user interfaces[edit]In commands processed by command processors, e.g., in scripts and typed in, the space character can cause problems as it has two possible functions: as part of a command or parameter, or as a parameter or name separator. Ambiguity can be prevented either by prohibiting embedded spaces, or by enclosing a name with embedded spaces between quote characters. Markup languages[edit]Some markup languages, such as SGML, preserve whitespace as written. Web markup languages such as XML and
HTML treat whitespace characters specially, including space characters, for programmers' convenience. One or more space characters read by conforming display-time processors of those markup languages are collapsed to 0 or 1 space, depending on their semantic context. For example, double (or more) spaces within text are
collapsed to a single space, and spaces which appear on either side of the " In XML attribute values, sequences of whitespace characters are treated as a single space when the document is read
by a parser.[30] Whitespace in XML element content is not changed in this way by the parser, but an application receiving information from the parser may choose to apply similar rules to element content. An XML document author can use the In most HTML elements, a sequence of whitespace characters is treated as a single inter-word separator, which may manifest as a single space character when rendering text in a language that normally inserts such space between words.[31] Conforming HTML
renderers are required to apply a more literal treatment of whitespace within a few prescribed elements, such as the In both XML and HTML, the non-breaking space character, along with other non-"standard" spaces, is not treated as collapsible "whitespace", so it is not subject to the rules above. File names[edit]Such usage is similar to multiword file names written for operating systems and applications that are confused by embedded space codes—such file names instead use an underscore (_) as a word separator, as_in_this_phrase. Another such symbol was U+2422␢ BLANK SYMBOL. This was used in the early years of computer programming when writing on coding forms. Keypunch operators immediately recognized the symbol as an "explicit space".[16] It was used in BCDIC,[16] EBCDIC,[16] and ASCII-1963.[16] See also[edit]
References[edit]
External links[edit]
Can we give more than one space in HTML?The simplest way to add a space in HTML (besides hitting the spacebar) is with the non-breaking space entity, written as or . Multiple adjacent non-breaking spaces won't be collapsed by the browser, letting you “force” several visible spaces between words or other page elements.
What is spacing in HTML?The word-spacing property is used to specify the space between the words in a text.
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