De bedste HTML- og HTML5-selvstudier

HyperText Markup Language (HTML) er et markup-sprog, der bruges til at konstruere online-dokumenter og er grundlaget for de fleste websteder i dag. Et markup-sprog som HTML tillader os at

  • oprette links til andre dokumenter,
  • strukturere indholdet i vores dokument, og
  • tilskrive kontekst og betydning til indholdet af vores dokument.

Et HTML-dokument har to aspekter. Den indeholder strukturerede oplysninger (Markup) og tekst-links (HyperText) til andre dokumenter. Vi strukturerer vores sider ved hjælp af HTML-elementer. De er konstruktioner af det sprog, der giver struktur og betydning i vores dokument til browseren, og elementet linker til andre dokumenter over internettet.

Internettet blev oprindeligt oprettet for at gemme og præsentere statiske (uændrede) dokumenter. De aspekter af HTML, der blev diskuteret ovenfor, blev set perfekt i disse dokumenter, som manglede alt design og styling. De præsenterede strukturerede oplysninger, der indeholdt links til andre dokumenter.

HTML5 er den nyeste version eller specifikation af HTML. World Wide Web Consortium (W3C) er den organisation, der er ansvarlig for at udvikle standarder for World Wide Web, inklusive dem til HTML. Da websider og webapplikationer vokser mere komplekse, opdaterer W3C HTML's standarder.

HTML5 introducerer et væld af semantiske elementer. Selvom vi diskuterede, hvordan HTML hjalp med at give mening til vores dokument, var det først med HTML5s introduktion af semantiske elementer, at dets potentiale blev realiseret.

Et simpelt eksempel på HTML-dokument

   Page Title   

My First Heading

My first paragraph.

! DOCTYPE html: Definerer dette dokument som HTML5

html: Rodeelementet på en HTML-side

head: Elementet indeholder metaoplysninger om dokumentet

title: Elementet angiver en titel til dokumentet

body: Elementet indeholder det synlige sideindhold

h1: Elementet definerer en stor overskrift

p: Elementet definerer et afsnit

Selvstudier til start med HTML og HTML5

Det bedste sted at begynde at lære HTML er med freeCodeCamp's 2-timers introduktion til HTML-tutorial.

Så hvis du føler dig mere eventyrlysten, har vi et helt 12-timers kursus, der dækker HTML, HTML5 og CSS i detaljer.

Sidestruktur

For at oprette dine sider HTMLskal du vide, hvordan du strukturerer en side i HTML. Grundlæggende følger strukturen af ​​en side nedenstående rækkefølge:

   Title of the Page     

1 - Erklæringen skal altid være den første, der vises på en HTMLside og fortæller browseren, hvilken version af sproget der bruges. I dette tilfælde arbejder vi med HTML5.

2 - og tags fortæller webbrowseren, hvor HTMLkoden starter og slutter.

3 - og tags indeholder oplysninger om webstedet, for eksempel: stil, metatags, scripts osv ...

4 - og tags fortæller browseren, hvad sidetitlen er. Titlen kan ses ved at identificere fanen i din internetbrowser. Den tekst, der er defineret mellem disse tags, er også den tekst, der bruges som titel af søgemaskinerne, når de præsenterer siderne i resultaterne af en søgning.

5 - Mellem og tags placeres sideindholdet, hvilket er det, der vises i browseren.

Ændringer i HTML5

Introduktion af semantiske tags

I stedet for at bruge til alle andre containere er der flere semantiske (disse tags hjælper skærmlæsere, der bruges af synshandicappede) tags såsom . Så det tilrådes at bruge disse tags i stedet for det generiske .

HTML-elementer

Elementer er byggestenene i HTML, der beskriver strukturen og indholdet af en webside. De er "Markup" -delen af ​​HyperText Markup Language (HTML).

HTML-syntaks bruger vinkelparenteserne (””) til at holde navnet på et HTML-element. Elementer har normalt et åbningstag og et afsluttende tag og giver information om det indhold, de indeholder. Forskellen mellem de to er, at det afsluttende tag har en skråstreg.

Her er et eksempel på p-elementet (

This is a paragraph.

Opening and closing tags should match, otherwise the browser may display content in an unexpected way.

XKCD comic showing the text

Self-closing Elements

Some HTML elements are self-closing, meaning they don’t have a separate closing tag. Self-closing elements typically insert something into your document.

An example is the br element (

), which inserts a line break in text. Formerly, self-closing tags had the forward slash inside them (

HTML Element Functionality

There are many available HTML elements. Here’s a list of some of the functions they perform:

  • give information about the web page itself (the metadata)
  • structure the content of the page into sections
  • embed images, videos, audio clips, or other multimedia
  • create lists, tables, and forms
  • give more information about certain text content
  • link to stylesheets which have rules about how the browser should display the page
  • add scripts to make a page more interactive and dynamic

Nesting HTML Elements

You can nest elements within other elements in an HTML document. This helps define the structure of the page. Just make sure the tags close from the inside-most element first.

Correct:

This is a paragraph that contains a span element.

Incorrect:

This is a paragraph that contains a span element.

Block-level and Inline Elements

Elements come in two general categories, known as block-level and inline. Block-level elements automatically start on a new line while inline elements sit within surrounding content.

Elements that help structure the page into sections, such as a navigation bar, headings, and paragraphs, are typically block-level elements. Elements that insert or give more information about content are generally inline, such as links or images.

The HTML Element

There’s an element that’s used to contain the other markup for an HTML document. It’s also known as the “root” element because it’s the parent of the other HTML elements and the content of a page.

Here’s an example of a page with a head element, a body element, and one paragraph:

I'm a paragraph

The HEAD Element

This is the container for processing information and metadata for an HTML document.

The BODY Element

This is a container for the displayable content of an HTML document.

...

The P Element

Creates a paragraph, perhaps the most common block level element.

...

The A(Link) Element

Creates a hyperlink to direct visitors to another page or resource.

...

Images in HTML

You can define images by using the tag. It does not have a closing tag since it can contain only attributes. To insert an image you define the source and an alternative text which is displayed when the image can not be rendered.

src - This attribute provides the url to the image present either on your P.C./Laptop or to be included from some other website. Remember the link provided should not be broken otherwise the image will not be produced on your webpage.

alt - This attribute is used to overcome the problem of broken image or incapability of your browser to produce image on webpage. This attribute, as the name suggests, provides an “Alternative” to an image which is some ‘TEXT’ describing the image.

Example

To define height and width of an image you can use the height and width attribute:

You can also define border thickness (0 means no border):

Align an image:

You are also able to use styles within a style attribute:

How to use links in HTML

In HTML you can use the tag to create a link. For example you can write freeCodeCamp to create a link to freeCodeCamp’s website.

Links are found in nearly all web pages. Links allow users to click their way from page to page.

HTML links are hyperlinks. You can click on a link and jump to another document.

When you move the mouse over a link, the mouse arrow will turn into a little hand.

Note: A link does not have to be text. It can be an image or any other HTML element.

In HTML, links are defined with the tag:

link text

Example

Visit our site for tutorials

The href attribute specifies the destination address (//www.freecodecamp.org) of the link.

The link text is the visible part (Visit our site for tutorials).

Clicking on the link text will send you to the specified address.

How to Use Lists in HTML

Lists are used to specify a set of consecutive items or related information in a well formed and semantic way, such as a list of ingredients or a list of procedural steps.

HTML markup has three different types of lists - ordered, unordered and description lists.

Ordered Lists

An ordered list is used to group a set of related items, in a specific order. This list is created with

    tag. Each list item is surrounded with
  1. tag.

    Code
    
            
    1. Mix ingredients
    2. Bake in oven for an hour
    3. Allow to stand for ten minutes
    Example
    1. Mix ingredients
    2. Bake in oven for an hour
    3. Allow to stand for ten minutes

    Unordered Lists

    An unordered list is used to group a set of related items, in no particular order. This list is created with

      tag. Each list item is surrounded with
    • tag.

      Code
      
                
      • Chocolate Cake
      • Black Forest Cake
      • Pineapple Cake

      Example

      • Chocolate Cake
      • Black Forest Cake
      • Pineapple Cake

      Description Lists

      A description list is used to specify a list of terms and their descriptions. This list is created with

      tag. Each list item is surrounded with
      tag.

      Code
      
                  
      Bread
      A baked food made of flour.
      Coffee
      A drink made from roasted coffee beans.
      Output

      Bread A baked food made of flour. Coffee A drink made from roasted coffee beans.

      Styling List

      You can also control the style of the list. You can use list-style property of lists. Your list can be bullets, squares, in Roman numerals, or can be images if you want.

      list-style property is shorthand for list-style-type, list-style-position, list-style-image.