What you are looking at is a web text editor. There is a preview box at the bottom of every editing box enabling you to see how your post will look before you actually submit it. If you fancy, you can totally ignore this feature and just write your post as normal. But if you would like to link to things in your posts, or perhaps make your text bold or in italics, then clicking in the relevant buttons will help you. The editor will place stars around what you have selected and will then know that you want that area styled. Just have a go at creating links, emphasising words and you will soon get the hang of it. Remember you can always preview it in the box below the text editor. If you know how, you may use your own html. However not all html is allowed, and things like images and styling will be stripped from your post.