Current course:

HTML tags

Every HTML file must start with the <html> tag. This tells the browser what type of file it is so it can properly decode the scripts.
The stuff in the <body> is VISIBLE to the User. The stuff in the <head> is invisible, except for the title.

HTML is NOT case sensitive, but choose upper or lower, don't use both. (I recommend lowercase)

TAGS
<> angle brackets tell the browser to read the text as script tags.
<> is an opening tag. Ex: <HTML><br/> </> is a closing tag. Ex: </HTML><br/>

Brackets hold the COMMAND and the ATTRIBUTES (options) for that command;
You can have many attributes in one TAG. Attributes have specific values.

Example: <hr width="200" align="left" />
Tags that do not hold content should "self close" - eg. <br/> or <hr/>
While it is acceptable to not close these tags in HTML, xHTML requires all tags to closed, therefore it's considered best practice to close all tags.