Well, it stands for Hypertext Markup Language. You won't have to know that, but now if somebody asks you, you can brag about it. If you're planning to make an effective site you will eventually have to learn the language even though there are programs such as FrontPage which will create the HTML text for you. I use FrontPage mostly for creating tables or typing long tutorials such as the 7 day tutorials. Sometimes I go through the HTML because that's how I started with all this.
Tags usually work in pairs.
A start of an operation and an end. One last thing, do my tags have to be CAPS Nope, it's entirely up to you. I tend to lean to the BIG letters just because it separates the HTML tags from the rest of the page, and usually makes it easier to read. It's entirely up to you. There are many things which can go inside the head tag.