This page illustrates how you can write proper HTML using only a text editor, such as Windows Notepad. You can also download a free text editor, such as Crimson Editor, which is better than Notepad.
There is a small graphic after the period at the end of this sentence. The graphic is in a file. The file is inside a folder named "images."
Link: Yahoo!
Another link: Another Web page
Note the way the BR tag works in the two lines above.