non-breaking space
<!--This is a comment. Comments are not displayed in the browser-->
<p>This is a paragraph.</p>
Unordered:
<!DOCTYPE html>
<html>
<body>
<h2>Unordered List with Circle Bullets</h2>
<ul style="list-style-type:circle">
<li>Apples</li>
<li>Bananas</li>
<li>Lemons</li>
<li>Oranges</li>
</ul>
</body>
</html>
<ul style="list-style-type:disc">
<li>Coffee</li>
<li>Tea
<li>Milk</li>
</ul>
<ul style="list-style-type:square">
<li>Coffee</li>
<li>Tea
<li>Milk</li>
</ul>
<ul style="list-style-type:none">
<li>Coffee</li>
<li>Tea
<li>Milk</li>
</ul>
Table without boxes
http://www.w3schools.com/html/tryit.asp?filename=tryhtml_table
<!DOCTYPE html>
<html>
<body>
<table style="width:100%">
<tr>
<td>Jill</td>
<td>Smith</td>
<td>50</td>
</tr>
<tr>
<td>Eve</td>
<td>Jackson</td>
<td>94</td>
</tr>
<tr>
<td>John</td>
<td>Doe</td>
<td>80</td>
</tr>
</table>
</body>
</html>
table single line borders
http://www.w3schools.com/html/tryit.asp?filename=tryhtml_table_collapse
<!DOCTYPE html>
<html>
<head>
<style>
table, th, td {
border: 1px solid black;
border-collapse: collapse;
}
</style>
</head>
<body>
<table style="width:100%">
<tr>
<td>Jill</td>
<td>Smith</td>
<td>50</td>
</tr>
<tr>
<td>Eve</td>
<td>Jackson</td>
<td>94</td>
</tr>
<tr>
<td>John</td>
<td>Doe</td>
<td>80</td>
</tr>
</table>
</body>
</html>
table with boxes
http://www.w3schools.com/html/tryit.asp?filename=tryhtml_table_border_attribute
<!DOCTYPE html>
<html>
<body>
<table border="1" style="width:100%">
<tr>
<td>Jill</td>
<td>Smith</td>
<td>50</td>
</tr>
<tr>
<td>Eve</td>
<td>Jackson</td>
<td>94</td>
</tr>
<tr>
<td>John</td>
<td>Doe</td>
<td>80</td>
</tr>
</table>
</body>
</html>
3x3 table with red and yellow background colors
http://www.w3schools.com/tags/tag_col.asp
<!DOCTYPE html>
<html>
<head>
<style>
table, th, td {
border: 1px solid black;
}
</style>
</head>
<body>
<table>
<colgroup>
<col span="2" style="background-color:red">
<col style="background-color:yellow">
</colgroup>
<tr>
<th>ISBN</th>
<th>Title</th>
<th>Price</th>
</tr>
<tr>
<td>3476896</td>
<td>My first HTML</td>
<td>$53</td>
</tr>
<tr>
<td>5869207</td>
<td>My first CSS</td>
<td>$49</td>
</tr>
</table>
</body>
</html>
http://www.w3schools.com/tags/tag_comment.asp
You can also use the comment tag to "hide" scripts from browsers without support for scripts (so they don't show them as plain text):
<script type="text/javascript">
<!--
function displayMsg()
{
alert("Hello World!")
}
//-->
</script>
Note: The two forward slashes at the end of comment line (//) is the JavaScript comment symbol. This prevents JavaScript from executing the --> tag.