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HTML

              
                This is just some random text. 

We can tag it, but we don't have to.

Notice that the browser does not honor any whitespace, except 
single
    whitespace
      characters
        and
          single
            carriage returns (ENTER key).



<h1>Normal Document Flow in HTML</h1>
<div>This is a div.</div>

<div>
  This is a div. 
  With some ENTER keys.
  This is a div.
</div>

<div>This is a div.</div>


<div>This is a div.</div>

<span>This is a span.</span>

<div>This is a div.</div>

<span>This is a span.</span> <span>This is a span.</span>

<span>This is a span.</span>
<span>This is a span.</span>

<div>A div is a block-level element.</div>
<span>A span is an inline element.</div>
              
            
!

CSS

              
                h1 { background: plum; border: 1px solid blue }

/* 
div { background: plum; border: 1px solid blue } 
*/

/* 
p { background: plum; border: 1px solid blue } 
*/


/*
HTML Conclusions:
1. HTML elements flow on a web page (web document), kind of like a river.
2. This what normal document flow looks like:
----------------
| ------------> |
| ------------> |
| ------------> |
| ------------> |
| ------------> |
-----------------
Normal document flow means that elements flow:
2.1. top-to-bottom
2.2. left-to-right

3. Normal document flow when we only have divs:

-----------------------------
| <div>..............</div> |
| <div>..............</div> |
| <div>..............</div> |
| <div>..............</div> |
| <div>..............</div> |
| <div>..............</div> |
| <div>..............</div> |
| <div>..............</div> |
-----------------------------

Regardless of how long is the text content inside a div, each div will fill the entire available width of its parent. That's why the <div> element is what's known as a block-level element. In a normal document flow, a bunch of divs look like a bunch of blocks stacked on top of one another.

4. Normal document flow when we have span tags only:

------------------------------------------------------
| <span>...</span> <span>...</span> <span>...</span> |
| <span>...</span> <span>...</span> <span>...</span> |
| <span>...</span> <span>...</span> <span>...</span> |
| <span>...</span> <span>...</span> <span>...</span> |
| <span>...</span> <span>...</span> <span>...</span> |
| <span>...</span> <span>...</span> <span>...</span> |
| <span>...</span> <span>...</span> <span>...</span> |
| <span>...</span> <span>...</span> <span>...</span> |
                      ...etc...
------------------------------------------------------

This is why the <span> element is called an INLINE element.

*/

/* CSS Conclusions:
 3. We can comment out single lines in CSS files with two consecutive backslash characters.
 
 4. A multi-line comment starts with:
/* 
... and ends with: */

              
            
!

JS

              
                
              
            
!
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