What is the purpose of the sub tag? Physical formatting tags for HTML text
Tag
Tag used to specify the font in lowercase (subscript). Lowercase are reduced-size characters that appear offset downward relative to the rest of the characters in the line. In general, according to the generally accepted definition, symbols lowercase should be positioned below the baseline of the current line, but from all browsers the contents of the container Only Opera displays this way - the rest display characters a little higher.
The baseline is an imaginary line running along the bottom edge of the characters. Some letters (шч, ц, у, д, р, ф) partially extend beyond the baseline.
Attributes
Personal attributes: No.
- accesskey - Sets the shortcut key for focusing on an HTML element.
- class - specifies the name of the tag class or classes used in CSS (Cascading Style Sheets).
- dir - indicates the direction of the text within the element.
- - specifies the name of an HTML tag identifier that can be used as an “anchor” or in style sheets.
- lang - indicates the language in which the text inside the HTML element is written.
- style - required to use built-in CSS styles to tag.
- tabindex - sets the tab order between elements (Tab key).
- title - displays a tooltip when you hover the mouse over an HTML element.
Tag type
Purpose: text (strings).
Tag model: inline (built-in, line level).
May contain: inline tags, plain text and HTML special characters(mnemonics).
Opening tag: necessary. Closing tag: necessary.
Syntax
contentHTML Example: Using the SUB Tag
t n= n!
Here is a description of physical formatting tags. Some of them are not recommended for use by the HTML 4.0 specification for the reasons given above. Some tags have been deprecated by the HTML 4.0 specification, but they continue to be supported by browsers.
Tag
Tag displays text in bold font. In most cases it is recommended instead of a tag use logical formatting tag . For example:
This bold font.
Rice. 1.2. Examples of physical text formatting (Netscape browser)
Tag
Tag displays text in italics. For most cases, it is recommended to use tags instead of this tag , , or , since the latter better reflect the purpose of the selected text. For example:
Selection italics
Tag
Tag displays text in monospace font. For most cases, it is better to use tags instead of this tag ,
or . Example:
This monospace font.
Tag
Tag displays text underlined. Canceled tag. It is recommended to use tags instead or . For example:
Example underscores text.
Tags And
Tags And display text with a strikethrough horizontal line. Canceled tag. The tag should be used instead . For example:
Example crossed out text.
Currently tag is not supported by all browsers, so for now it is recommended to use in combination with a tag . Namely, inside the container tag you can add a couple of tags
....
Tag
Tag displays text in a font larger (than the unlabeled part of the text) size. Instead of this element it is better to use or title tags, e.g.
Font more size.
Tag
Tag displays text in a smaller font size. Since there is no tag in HTML that is the opposite of the tag , then for these purposes you can use the tag . Most browsers support nested tags , however, this approach is not recommended. For example:
Font less size.
Tag
Tag moves text below line level and displays it (if possible) in a smaller font size. Convenient to use for mathematical indices. For example:
Example font for lower index.
Tag
Tag moves text above line level and displays it (if possible) in a smaller font size. Convenient to use for assigning powers of numbers in mathematics. For example:
Example font for upper index.
Tag
Tag
Tag
Tag container is analogous to a block level tag The Microsoft Internet Explorer browser additionally allows the use of the following tag parameters: DIR, DATAFLD, DATAFORMATAS, DATASRC. A description of the parameters can be found in the second part of the book. Rice. 1.3. Using nested text formatting tags Formatting tags can be nested within each other. In this case, you need to carefully ensure that one container is located entirely in another container. In Fig. Figure 1.3 shows an example of nesting an italic element within a bold element. The following HTML code fragment is used: This bold font. This italics. And here is the text bold and italic Tag
Tag specifies font options. It refers to text-level physical formatting tags. Assigning font parameters directly in the document text violates the basic idea of separating the content of the document and describing the form of presentation of the document. Therefore, in the HTML 4.0 specification this tag, as well as the tag Despite these dire warnings, it appears that physical formatting can be considered acceptable for the simplest documents. In addition, the easiest way to start learning the basics of formatting is with the rules for directly specifying element formats. A novice developer still has to grow up to style design. Tag refers to sequential elements, so cannot include block level elements, e.g. Or The following parameters can be set for a tag: FACE, SIZE and COLOR. Note that the Netscape browser also allows the use of two additional parameters: POINT-SIZE and WEIGHT, the description of which is omitted. The FACE parameter is used to specify the type of font in which the user's viewer will display text (if such a font is available on the computer). The value of this parameter is the name of the font, which must exactly match the name of the font that the user has. If no such font is found, this instruction will be ignored and the default font will be used. You can specify one or several font names, separating them with commas. This is a very useful property, since different systems may have almost identical fonts with different names. Another important quality is to set preferences for using fonts. The font list is scanned from left to right. If the user's computer does not have the first font in the list, an attempt is made to find the next font, and so on. Here is an example of using the FACE parameter: An example of specifying a font name. In Fig. Figure 1.4 shows how the Netscape browser displays an example. In the example, the Verdana font is indicated as the preferred font; if it is absent, the Arial font will be used, etc. Rice. 1.4. Netscape browser example display This parameter is used to specify font sizes in arbitrary units from 1 to 7. The specific font size depends on the viewer you are using. It is generally accepted that a “normal” font size corresponds to a value of 3. Default font size settings, as well as the amount of absolute font size change, vary between browsers. In Fig. Figure 1.5 shows the Netscape browser settings window, which sets the default fonts. The font size is indicated both as an absolute value (SIZE=2) and as a relative value (SIZE=+1). The latter method is often used in combination with setting the base font size using a tag Note
When specifying font sizes, entries like "2" and "+2" (unlike most programming languages, in which the unary "+" sign can be omitted) give fundamentally different results. Here's an example that uses different methods for assigning font sizes. An example display is shown in Fig. 1.6. Rice. 1.5. Netscape browser font settings window Rice. 1.6. Assigning font sizes Font size 1 Font size 2 Font size 3 Font size 4 Font size 5 Font size 6 Font size 7 This option sets the font color, which can be specified using standard names or in the #RRGGBB format. Here is an example of a document with multi-colored text. Green text Red text Tag Tag Note
Tag Note that for the tag The parameters can be exactly the same as for the tag , namely: FACE, SIZE and COLOR. The purpose and rules for writing parameters are similar. Note
Netscape browser does not allow FACE tag parameter Here is an example of using the tag Text written in the default font. Font size 2. Font size 4. Text after table The example above overrides the default font size twice. Initially it is 3 (default). Then it is set to 2, then 4. Pay attention to the display of this example (Fig. 1.7). It can be seen that for tables the purpose of the tag is Rice. 1.7. Displaying an example with a tag Text as subscript and superscript: This text contains subscript text. This text contains superscript text. Tag defines text as a subscript. A subscript looks like a character below a line. Similar text can be used in chemical formulas: H 2 O. Tag defines text as a superscript. A superscript looks like a character above a line. Superscript can be used for footnotes: WWW. Displays the font as a subscript. The text is positioned below the baseline of the remaining characters in the line and is reduced in size. Required.
Under the influence of hydroxylamine, aldehydes are converted into oximes: CH 3 CHO + NH 2 OH=CH 3 C(=NOH)H + H 2 O ✖
Each specification goes through several stages of approval. The living HTML standard (Living) stands out - it does not adhere to traditional version numbering, since it is under constant development and is updated regularly. Tag defines interlinear text. Interlinear text has half the height and appears below the baseline. Interlinear text can be used when writing chemical formulas, such as H 2 O. Tag defines superscript text. Superscript text is half the height and appears above the baseline. Superscript text can be used when writing footnotes, such as WWW. Tags And supported by all major browsers. Column DTD specifies in which document type the HTML 4.01/XHTML 1.0 DTD attribute is allowed. S=Strict, T=Transitional and F=Frameset. Tags And support the following standard attributes: More information about Standard Attributes. Tags And support the following event attributes: More information about
.
Text inside a table cell 
Description and use
Difference between HTML and XHTML
Standard Attributes
Event attributes
Attribute Meaning Description
onclick script
The script will be executed when clicked
ondblclick script
The script will be executed when you double click
onfocus script
The script will be executed when focus is received
onmousedown script
The script will be executed when the mouse button is pressed
onmousemove script
The script will be executed when the mouse cursor moves
onmouseout script
The script will be executed when the mouse cursor leaves the element
onmouseover script
The script will be executed when the mouse cursor is over the element
onmouseup script
The script will be executed when the mouse button is released
onkeydown script
The script will be executed when a key is pressed
onkeypress script
The script will be executed when a key is pressed and then released
onkeyup script
The script will be executed when the key is released
Description
Syntax
Text
Closing tag
Attributes
Similar to CSS
Example. Using a tag
Specification ?
Specification
Browsers: Desktop Mobile ?
Internet Explorer
Chrome Opera Safari Firefox
2
1
3.5
1
1
Android Firefox Mobile Opera Mobile Safari Mobile
1
1
6
1
HTML Tags And - Subscript and Superscript Text
Definition and Use
Browser support
Differences Between HTML and XHTML
Standard Attributes
Attribute
Meaning
Description
DTD
class
class_name
Specifies the class name for the element
STF
dir
rtl
ltrSpecifies the text direction for content in an element
STF
id
identifier
Specifies a unique identifier for an element
STF
lang
language_code
Specifies the language code for the element's content
STF
style
style_definition
Specifies an inline style for an element
STF
title
text
Indicates Additional information about the element
STF
xml:lang
language_code
Defines the language code for element content in XHTML documents
STF
Event Attributes
Attribute
Meaning
Description
DTD
onclick
script
Script launched on mouse click
STF
ondblclick
script
Double-click script
STF
onmousedown
script
Script to run when mouse button is pressed
STF
onmousemove
script
Script to run when the mouse pointer moves
STF
onmouseout
script
Script to run when the mouse pointer moves outside of an element
STF
onmouseover
script
Script run when the mouse pointer moves over an element
STF
onmouseup
script
Script to run when mouse button is released
STF
onkeydown
script
Script run on keypress
STF
onkeypress
script
Script run when a key is pressed and then released
STF
onkeyup
script
Script to run when the key is released
STF
