Bedeutung
A markup keyword wrapped in angle brackets that tells the browser what kind of element to create.
Ziel
Use the tag name when the target is a broad element type, such as every button or every link.
Markup
<header>...</header>Beispielanfrage
Change the style of all button tags inside the header.
Bedeutung
A complete piece of HTML, usually made from a start tag, content, and an end tag.
Ziel
Say element when you mean one visible part of the page, such as a title, card, or button.
Markup
<button>Menu</button>Beispielanfrage
Move the language switcher element next to the menu button.
Grundlagen
Attribute
Attribute
<a href="/ko">Home</a>
Bedeutung
Extra information written inside a start tag, such as href, class, id, src, or aria-label.
Ziel
Attributes are useful when the same tag appears many times but only one has a specific class, id, or label.
Markup
<a href="/ko">Home</a>Beispielanfrage
Add an aria-label attribute to the icon-only menu button.
Grundlagen
Opening and closing tag
Opening and closing tag
<section>Content</section>
Bedeutung
Many elements start with an opening tag and end with a matching closing tag.
Ziel
This helps when explaining where a section begins and ends in markup.
Hinweis
A missing closing tag can make the browser treat later content as part of the wrong element.
Markup
<section>Content</section>Beispielanfrage
Check that the card section has matching opening and closing tags.
Bedeutung
A declaration that tells the browser to render the document as modern HTML.
Ziel
It is usually handled by the framework and rarely edited during component work.
Markup
<!doctype html>Beispielanfrage
Do not change the document type; only edit the page component.
<html lang="ko">...</html>
Bedeutung
The root element that wraps the whole HTML document.
Ziel
The html element is used for document-wide settings such as language or theme attributes.
Markup
<html lang="ko">...</html>Beispielanfrage
Set the html lang attribute correctly for each locale.
<head><title>...</title></head>
Bedeutung
The document area for metadata, title, icons, SEO tags, and scripts that are not visible page content.
Ziel
Use this term when asking to change SEO title, description, canonical URL, or metadata.
Markup
<head><title>...</title></head>Beispielanfrage
Update the metadata title for the HTML structure terms page.
<body>Visible page</body>
Bedeutung
The document area that contains visible page content.
Ziel
Most layout, header, menu, and tool edits happen inside the body.
Markup
<body>Visible page</body>Beispielanfrage
Keep the body background consistent in light and dark mode.
<title>Engineering Tools for AI</title>
Bedeutung
The page title shown in the browser tab and often used by search engines.
Ziel
Use it when the visible H1 is fine but the browser or SEO title needs to change.
Markup
<title>Engineering Tools for AI</title>Beispielanfrage
Make the browser title more specific without changing the visible page heading.
<meta name="description" content="...">
Bedeutung
Metadata tags that describe the page, viewport, encoding, or social preview information.
Ziel
Meta descriptions affect previews and search snippets, not visible page text.
Markup
<meta name="description" content="...">Beispielanfrage
Update the meta description to mention searchable HTML terms.
Seitenbereiche
header
header
<header>...</header>
Bedeutung
A semantic region for introductory or top navigation content.
Ziel
Use header when targeting the site title, top navigation, theme button, language button, or menu button.
Markup
<header>...</header>Beispielanfrage
Move the language switcher inside the header controls next to the menu button.
Bedeutung
A semantic region for major navigation links.
Ziel
Use nav when editing category links, menu groups, or page navigation.
Markup
<nav>...</nav>Beispielanfrage
Group the menu links inside nav by Converter, Math, and Programming.
Bedeutung
The primary content area of a page. A page should generally have one main element.
Ziel
Use main when distinguishing page content from the header, footer, or menu.
Markup
<main>...</main>Beispielanfrage
Keep the floating menu above the main content without pushing it down.
Seitenbereiche
section
section
<section>...</section>
Bedeutung
A thematic grouping of related content, usually with a heading.
Ziel
Use section when targeting a large page block, such as hero, tools, or reference content.
Markup
<section>...</section>Beispielanfrage
Reduce the vertical padding of the tools section on mobile.
Seitenbereiche
article
article
<article>...</article>
Bedeutung
A self-contained content item, such as a card, post, reference entry, or result.
Ziel
Use article when each repeated card has its own title and body.
Markup
<article>...</article>Beispielanfrage
Make each term article more compact on desktop.
Bedeutung
A region for supporting content related to the main content, often a sidebar or note.
Ziel
Use aside when asking for a filter panel, side navigation, or supporting note to move.
Markup
<aside>...</aside>Beispielanfrage
Move the aside below the main content on mobile.
Seitenbereiche
footer
footer
<footer>...</footer>
Bedeutung
A bottom region for legal links, secondary navigation, contact information, or closing content.
Ziel
Use footer when targeting the page bottom rather than a section bottom.
Markup
<footer>...</footer>Beispielanfrage
Add a small legal link group to the footer.
Bedeutung
A heading element from h1 to h6 that gives structure to page content.
Ziel
Use heading level when asking to change the hierarchy, not only the visual size.
Hinweis
Do not choose h1 or h2 only for size; use CSS for visual size and headings for document structure.
Markup
<h1>Page title</h1>Beispielanfrage
Keep the page title as h1 and make card titles h2 or h3.
Bedeutung
A paragraph of text.
Ziel
Use paragraph when changing descriptive body text or its spacing.
Markup
<p>Description text.</p>Beispielanfrage
Shorten the paragraph under the hero title.
<a href="/ko/tools/math-prompt">Start</a>
Bedeutung
A link element that navigates to another page, route, file, or location.
Ziel
Use anchor or link when the element moves somewhere instead of performing an in-place action.
Markup
<a href="/ko/tools/math-prompt">Start</a>Beispielanfrage
Change the Browse tools link so it scrolls to the tools section.
Bedeutung
A group of related items, either unordered with ul or ordered with ol.
Ziel
Use list when asking to add, remove, reorder, or group repeated text items.
Markup
<ul><li>Item</li></ul>Beispielanfrage
Group the menu items into category lists.
<table><tr><td>Cell</td></tr></table>
Bedeutung
A structured grid of rows and cells for tabular data.
Ziel
Use table when the content is true row-and-column data, not just a visual grid of cards.
Markup
<table><tr><td>Cell</td></tr></table>Beispielanfrage
Use a table for truth table data instead of plain div blocks.
Inhalt
Code block
code / pre
<pre><code>npm run build</code></pre>
Bedeutung
code marks code text. pre keeps line breaks and spacing for multi-line code.
Ziel
Use code block when commands or examples must keep exact spacing.
Markup
<pre><code>npm run build</code></pre>Beispielanfrage
Show terminal commands in a pre/code block.
Inhalt
Strong and emphasis
strong / em
<strong>Important</strong>
Bedeutung
Semantic emphasis elements. strong means importance; em means stress emphasis.
Ziel
Use these for meaningful emphasis, not just decorative bold or italic styling.
Markup
<strong>Important</strong>Beispielanfrage
Use strong for the warning phrase inside the note.
<img src="/hero.png" alt="Tool preview">
Bedeutung
An element that displays an image file.
Ziel
Use image when asking to replace, resize, crop, or add alternative text to visual media.
Markup
<img src="/hero.png" alt="Tool preview">Beispielanfrage
Add a clear alt attribute to the hero image.
<img alt="Menu panel open">
Bedeutung
Text that describes an image for screen readers and when the image cannot load.
Ziel
Use alt when asking to improve accessibility or image meaning.
Hinweis
Decorative images can use empty alt text, but meaningful images need a useful description.
Markup
<img alt="Menu panel open">Beispielanfrage
Add alt text that explains what the screenshot shows.
Bedeutung
A vector graphic element often used for icons, diagrams, and scalable shapes.
Ziel
Use SVG when the visual is a simple shape or icon that should remain crisp.
Markup
<svg>...</svg>Beispielanfrage
Use an SVG icon for the menu button if there is no icon library available.
Formulare und Controls
Button
button
<button type="button">Menu</button>
Bedeutung
A control that performs an action when clicked or tapped.
Ziel
Use button when the control changes UI state, opens a menu, submits a form, or runs an action.
Hinweis
For navigation, a link is usually better than a button.
Markup
<button type="button">Menu</button>Beispielanfrage
Make the menu button close the language dropdown before opening the menu.
Formulare und Controls
Form
form
<form>...</form>
Bedeutung
A group of controls used to collect and submit user input.
Ziel
Use form when inputs belong to one submission or one input workflow.
Markup
<form>...</form>Beispielanfrage
Group the search input and category controls in one form-like control area.
Formulare und Controls
Label
label
<label for="search">Search</label>
Bedeutung
Text that names a form control.
Ziel
Use label when an input needs visible or screen-reader-friendly naming.
Markup
<label for="search">Search</label>Beispielanfrage
Add a label for the search input without cluttering the UI.
Formulare und Controls
Input
input
<input type="search" placeholder="Search">
Bedeutung
A field where the user types or chooses a value.
Ziel
Use input when targeting search fields, text fields, numbers, checkboxes, or other simple controls.
Markup
<input type="search" placeholder="Search">Beispielanfrage
Make the search input full width on mobile.
Formulare und Controls
Select
select
<select><option>English</option></select>
Bedeutung
A native dropdown control for choosing one option from a list.
Ziel
Use select when the control is a native form dropdown, not a custom menu panel.
Markup
<select><option>English</option></select>Beispielanfrage
Style the language select so the selected option is readable in dark mode.
Formulare und Controls
Textarea
textarea
<textarea>Long text</textarea>
Bedeutung
A multi-line text input.
Ziel
Use textarea when users need to paste or edit longer text.
Markup
<textarea>Long text</textarea>Beispielanfrage
Increase the textarea height for long prompt input.
<button class="icon-button">...</button>
Bedeutung
An attribute used to group elements for styling or behavior.
Ziel
Class is often the most practical way to target a repeated UI pattern.
Markup
<button class="icon-button">...</button>Beispielanfrage
Apply the same class to all menu category toggle buttons.
<section id="tools">...</section>
Bedeutung
A unique identifier for one element on a page.
Ziel
Use id when a link needs to scroll to a specific section or a label must connect to one input.
Hinweis
The same id should not be reused for multiple elements on one page.
Markup
<section id="tools">...</section>Beispielanfrage
Add an id to the tools section so the Browse tools link can scroll there.
<a href="/ko/reference/html-structure-terms">HTML</a>
Bedeutung
The destination URL or fragment for a link.
Ziel
Use href when a link points to the wrong page or section.
Markup
<a href="/ko/reference/html-structure-terms">HTML</a>Beispielanfrage
Change the Programming menu href to the new HTML structure terms page.
<img src="/images/example.png" alt="Example">
Bedeutung
The source file path for images, scripts, iframes, and similar media.
Ziel
Use src when an image or script is missing, wrong, or should be replaced.
Markup
<img src="/images/example.png" alt="Example">Beispielanfrage
Replace the image src with the new preview image path.
Attribute
Data attribute
data-*
<html data-theme="dark">
Bedeutung
Custom attributes used to store state or metadata on an element.
Ziel
Use data attributes when styling depends on a state such as theme, open, closed, or selected.
Markup
<html data-theme="dark">Beispielanfrage
Use data-theme on the html element to switch dark mode colors.
<div role="menu">...</div>
Bedeutung
An accessibility attribute that describes what kind of UI object an element represents.
Ziel
Use role when a custom component needs clear semantics, such as menu, dialog, tab, or alert.
Hinweis
Native semantic elements are usually better than adding role to a generic div.
Markup
<div role="menu">...</div>Beispielanfrage
Give the custom language list an appropriate menu role.
Barrierefreiheit
aria-label
aria-label
<button aria-label="Toggle menu">...</button>
Bedeutung
A text label for assistive technologies when visible text is missing or insufficient.
Ziel
Use aria-label for icon-only controls such as menu, search, close, or theme buttons.
Markup
<button aria-label="Toggle menu">...</button>Beispielanfrage
Add an aria-label that clearly names the hamburger menu button.
Barrierefreiheit
aria-expanded
aria-expanded
<button aria-expanded="false">Menu</button>
Bedeutung
An accessibility attribute that tells whether a controlled panel is open or closed.
Ziel
Use it for dropdown buttons, accordions, and menu toggles.
Markup
<button aria-expanded="false">Menu</button>Beispielanfrage
Update aria-expanded when the menu category opens or closes.
Beziehungen
Parent and child
Parent and child
<nav><a>Link</a></nav>
Bedeutung
A parent element contains child elements inside it.
Ziel
Use this when the target depends on where it is located, such as links inside nav or buttons inside header.
Markup
<nav><a>Link</a></nav>Beispielanfrage
Style only the links that are children of the header nav.
Beziehungen
Sibling
Sibling
<button /> <button />
Bedeutung
Elements that share the same parent are siblings.
Ziel
Use sibling when spacing or interaction depends on neighboring items.
Markup
<button /> <button />Beispielanfrage
Reduce the gap between sibling header buttons.
Beziehungen
Nesting
Nesting
<section><article><h2>Title</h2></article></section>
Bedeutung
The structure created when elements are placed inside other elements.
Ziel
Use nesting when explaining exactly which inner element should change.
Markup
<section><article><h2>Title</h2></article></section>Beispielanfrage
In each card, move the request example below the property chips.
Beziehungen
Wrapper
Wrapper
<div class="container">...</div>
Bedeutung
An element used mainly to group, constrain, or position other elements.
Ziel
Use wrapper when the layout needs a surrounding element rather than changes to each child.
Markup
<div class="container">...</div>Beispielanfrage
Add a wrapper around the header controls so the dropdown can align to the right.
Beziehungen
Container
Container
<div class="container">Page content</div>
Bedeutung
A wrapper that keeps page content aligned and constrained to a readable width.
Ziel
Use container when changing the overall content width or side padding.
Markup
<div class="container">Page content</div>Beispielanfrage
Make the main content container slightly narrower on desktop.
Beziehungen
Fragment
Fragment
<>...</>
Bedeutung
A wrapper used in React to group elements without adding an extra DOM element.
Ziel
Use fragment when grouping elements without affecting layout or CSS selectors.
Markup
<>...</>Beispielanfrage
Use a fragment instead of adding an unnecessary wrapper div.
Barrierefreiheit
Semantic HTML
Semantic HTML
<main><section><h1>...</h1></section></main>
Bedeutung
HTML that uses elements according to their meaning, not only their visual appearance.
Ziel
Use semantic HTML when improving structure, accessibility, SEO, or maintainability.
Markup
<main><section><h1>...</h1></section></main>Beispielanfrage
Use semantic HTML for the reference page sections instead of generic divs everywhere.
Barrierefreiheit
Landmark
Landmark
<header> <nav> <main> <footer>
Bedeutung
Important page regions that help assistive technology users navigate quickly.
Ziel
Header, nav, main, aside, and footer can act as landmarks.
Markup
<header> <nav> <main> <footer>Beispielanfrage
Keep one clear main landmark on each page.
Barrierefreiheit
Accessible name
Accessible name
<button aria-label="Open menu">☰</button>
Bedeutung
The name assistive technology uses to announce a control.
Ziel
Use accessible name when a control is visually clear but not named for screen readers.
Markup
<button aria-label="Open menu">☰</button>Beispielanfrage
Give the theme toggle a clear accessible name in every locale.
Barrierefreiheit
tabindex
tabindex
<button tabindex="0">Action</button>
Bedeutung
An attribute that can affect keyboard focus order.
Ziel
Use it carefully when custom controls are not reachable by keyboard.
Hinweis
Positive tabindex values can create confusing keyboard order. Native focus order is usually better.
Markup
<button tabindex="0">Action</button>Beispielanfrage
Avoid positive tabindex values and keep keyboard order natural.