OFFERED BY Duke UNIVERSITY
https://www.dukelearntoprogram.com

Let’s begin to learn how to think like a programmer:

analyzing problems, designing solutions called algorithms, and translating your algorithms into programs.

Reading document please, so that you will know what methods you can use in a programming language.

Use https://codepen.io to play around !

  • HTML is [not] a programming language but rather a Markup Language.

  • HTML is used by web browsers to display a webpage.

Note: You may have written documents in which you select text and make it bold or underlined or italics, [this is a way of marking up the text to display in certain ways ! ]

Metadata Elements

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<html>
  - specifies using HTML standard
  - contains all other elements

<head>
  - information about the page: title, css, scripts, ...

  <title>
    - specifies page title
    - nested inside <head></head> tags

etc...

Sectioning Elements

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<body>
  - contains all items seen on page

  <div>
    - defines section of webpage
    - [useful for grouping elements together to use CSS styling ! ]

  <h1>
    - section header
    - also <h2>, <h3>, ..., <h6>

  <p>
    - paragraphs.

etc...

Semantic or Style HTML Tags

Tags surround [text]/[page elements]

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<b>Make text stylistically different, Traditionally bold face, but can change</b>

eg:
If you have trouble seeing, then it's(<b></b>) a semantics/meaning
to helps screen reader to change how text is read to you(a blind user).

Adding Images, Audios/Videos

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<img src="http://xyz.png" width="75%" />
<img src="http://xyz.png" />

Note:

We can add Options(eg: src, width) in the image tags,
which give information about what we're doing.

Some Options are required!(eg: src, which means source),
because of that we have to specify what image we want to display.

What to use for src=”..” ?

In some cases, there may be concern with the person, organization or group that create the photo you display on a webpage you create. The creator has certain rights called copyrights.

Many images are in the public_domain and are not copyrighted.(eg: Wikimedia commons website)

Some images have what are called creative commons licenses, which specify how you can use the images, and some creative_commons_images are not copyrighted.

Images Storage

In some cases, there may be storage/hosting concerns.

Where are the images stored that you’ve included on your webpage? And who pays.

我曾经自建图床

Suppose one million people view your webpage, it means that the image is sent from the website which stores it, across the Internet to one million users that might be scattered all over the world! Someone pays, even if it’s not you.

Inline-Linking/Hot-Linking

When you use a URL in a webpage you create as part of an IMG tag,
you’ve included what’s called an Inline Linking, also called Hot Linking.
It means that the image is stored on another site but visually it appears in the site you create.

If you create a webpage with lots of views or traffic, there may be storage costs or server costs that might be a concern. => Thus some sites don’t allow hot-linking!

Further reason and solution.

Linking Pages Together

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<a href="https://asd.org/en-US/HTML">EXAMPLE_LINKS</a>

Note:

a means anchor.
href is required!

You must specify some text between the start and end anchor tag,
and this text will be clickable to take you to an another website.

Lists

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// unordered list
<ul>
  <li></li>
  <li></li>
  <li></li>
</ul>

// ordered list
<ol>
  <li></li>
  <li></li>
  <li></li>
</ol>

li tag stands for list items, [is required],
and are the only type of tag you can put as direct children of ul/ol tag.

inside li tags we can put much more than just text,
we can put images, links or even another list.

Tables

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<table>
<tr> => table row
<th> => table header
<td> => table data

Test your webpage

You can use private browsing to be sure that you are behaving like an anonymous user,
rather than being logged in as yourself when looking at a webpage.

eg: to be sure that you can see images.

Be aware of…

Making a webpage good isn’t easy.

Webpages can be displayed on different types of divices, such as your laptop, your phone.

Webpages can be used by different types of people, such as normal user, blind user.

…