When you have a blog post set on 'compose', it is much easier to do use, especially if you don't have much experience with websites.
In the 'compose' setting, you are able to use the icons above to control what happens to your text. For instance, perhaps you think a word is particularly important and want to highlight it, you can do so from the controls above, like this.
Then you perhaps want to link to your main website, or a newspaper story you saw. You do this by first highlighting a selection of text, and then doing this...
Now, unless you are keen to do all the coding yourself, there is no need to cause yourself stress by trying to remember all of the tags for everything you want to do! However there are occasions when being even slightly familiar with this 'html' box will be useful.
A big one is to embed YouTube videos. Once you have copied the code from underneath the YouTube video, you just paste it here on a new line, like this:
The amazing thing is that mess of nonsensical characters will make something wonderful happen when your blog post is published...!