All of the tags we've seen so far come in pairs: an opening tag, and a matching closing tag. Together, these two tags define a single thing called an element. For example, this paragraph is a single "p" element, formed by a "p" tag and a "/p" tag that together indicate where the element starts and ends.
Most elements have two tags and can contain text or other elements in between their tags. However, there are a few elements—called "empty elements"—can't contain anything, so they must start and end at the same place and only need one tag. I recommend putting a slash / at the end of such tags to make it obvious that they are self-closing. A very useful example is the img element for displaying images:
If you find or upload an image somewhere on the internet so that it has a web address, you can display it in an img element by putting the image's address in the src attribute, which works pretty much the same way href does in links. I'll talk more about sharing images and web pages on the internet later.
Another empty element is hr, which stands for Horizontal Rule. It just draws a long horizontal line for dividing sections.
Make sure you take a look at how img, hr, and br are used in the source script. I just have one more page of HTML to show you before we get to the fun stuff, so when you're ready, let's move on!