The id Attribute

The HTML id attribute is used to specify a unique id for an HTML element (the value must be unique within the HTML document).
Using The id Attribute
The id attribute is used by CSS or JavaScript to perform certain tasks for the element with the specific id value.
In CSS, to select an element with a specific id, write a hash (#) character, followed by the id of the element:


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Indicate the current page’s location within a navigational hierarchy that automatically adds separators via CSS.



Convey meaning through color with a handful of color utility classes. Includes support for styling links with hover states, too.


Toggle floats on any element, across any breakpoint, using our responsive float utilities. 0460286885

Composition vs Inheritance

React has a powerful composition model, and we recommend using composition instead of inheritance to reuse code between components.
In this section, we will consider a few problems where developers new to React often reach for inheritance, and show how we can solve them with composition.


Related Content


What Is React? React is a declarative, efficient, and flexible JavaScript library for building user interfaces.
It lets you compose complex UIs from small and isolated pieces of code called “components”. React has a few different kinds of components, but we’ll start with React.Component subclasses:


Paragraphs A paragraph always starts on a new line, and browsers automatically add some white space (a margin) before and after a paragraph.


State and Lifecycle This page introduces the concept of state and lifecycle in a React component. You can find a detailed component API reference here.
Consider the ticking clock example from one of the previous sections. In Rendering Elements, we have only learned one way to update the UI. We call ReactDOM.render() to change the rendered output:


HTML Audio The controls attribute adds audio controls, like play, pause, and volume.
The source element allows you to specify alternative audio files which the browser may choose from. The browser will use the first recognized format.
The text between the audio tags will only be displayed in browsers that do not support the audio element.


Progress Documentation and examples for using Bootstrap custom progress bars featuring support for stacked bars, animated backgrounds, and text labels.


What is SVG? SVG stands for Scalable Vector Graphics
SVG is used to define graphics for the Web
SVG is a W3C recommendation
The HTML svg Element
The HTML svg element is a container for SVG graphics.
SVG has several methods for drawing paths, boxes, circles, text, and graphic images.