Elements are all lower case.
Most elements should be closed
hr - horizontal rule
Images don't need to be closed either.
for example, the address in an url should be in quotes. Same for address of an image.
Set the width and height
It is ok to use auto for the height, percentages are my preference for the width
Don't use spaces around = signs
<img src="smokey.jpg" alt="cat">
<img src = "smokey.jpg" alt = "cat">
Where to find the escape characters:
HTML Entitiesthe other title is an attribute, not a tag, and is a tool tip
Always include html, head, and body tags
Include the lang attribute in the header. We use "en-us"